RECORD OF DECISION
SUTTON BROOK DISPOSAL AREA SUPERFUND SITE
TEWKSBURY, MASSACHUSETTS
MIDDLESEX COUNTY
SEPTEMBER 2007
Prepared by:
United States Environmental Protection Agency
New England Region - Region 1
One Congress Street
Suite 1100 (HBO)
Boston, Massachusetts 02114
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Record of Decision
Table of Contents
PARTI: THE DECLARATION
A. STATEMENT OF BASIS AND PURPOSE
B. ASSESSMENT OF SITE
C. DESCRIPTION OF SELECTED REMEDY
D. STATUTORY DETERMINATIONS
E. SPECIAL FINDINGS
F. ROD DATA CERTIFICATION CHECKLIST
G. AUTHORIZING SIGNATURE
PART 2: THE DECISION SUMMARY
A. SITE NAME, LOCATION AND BRIEF DESCRIPTION
B. SITE HISTORY AND ENFORCEMENT ACTIVITIES
1. History of Site Activities
2. History of Federal and State Investigations and Removal and Remedial Actions
3. History of CERCLA Enforcement Activities
C. COMMUNITY PARTICIPATION
D. SCOPE AND ROLE OF OPERABLE UNIT OR RESPONSE ACTION
E. SITE CHARACTERISTICS
F. CURRENT AND POTENTIAL FUTURE SITE AND RESOURCE USES
1, Land Uses
2. Groundwater Uses
G. SUMMARY OF SITE RISKS
1. Human Health Risks
2. Ecological Risks
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Table of Contents
3. Basis for Response Action
H. REMEDIATION OBJECTIVES
I. DEVELOPMENT AND SCREENING OF ALTERNATIVES
J. DESCRIPTION OF ALTERNATIVES
1, Source Control (SC) Alternatives Analyzed
2, Management of Migration (MM) Alternatives Analyzed
K. SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
L. THE SELECTED REMEDY
M. STATUTORY DETERMINATIONS
N. DOCUMENTATION OF SIGNIFICANT CHANGES
O. STATE ROLE
PART 3; THE RESPONSIVENESS SUMMARY
A. Questions and Comments Regarding Consolidation of Soils from Other Areas and
Capping of the Landfill Lobes
B. Questions and Comments Regarding the Approach to Groundwater Cleanup
C. Questions and Comments Regarding the Scope of the Remedial Investigation and
Feasibility Study (RI/FS)
D. Questions and Comments Regarding Liability, Enforcement, and the Timetable for
Remedy Implementation
APPENDICES
Appendix A: State DEP Letter of Concurrence
Appendix B: Groundwater Use and Value Determination
Appendix C; Figures
Appendix D: Tables
Appendix E: Administrative Record Index and Guidance Documents
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Part 1: The Declaration
DECLARATION FOR THE RECORD OF DECISION
Sutton Brook Disposal Area
Tewksbury, Massachusetts
CERCLIS No. MAD980520696
A. STATEMENT OF BASIS AND PURPOSE
This decision document presents the selected remedial action for the Sutton Brook Disposal Area
Site (Site), in Tewksbury, Massachusetts, which was chosen in accordance with the
Comprehensive Environmental Response, Compensation and Liability Act of 1980, as amended
(CERCLA), 42 U.S.C. § 9601 et seq., and, to the extent practicable, the National Oil and
Hazardous Substances Pollution Contingency Plan (NCP), 40 C.F.R. Part 300 et seq., as
amended. The Director of the Office of Site Remediation and Restoration (OSRR) has been
delegated the authority to approve this Record of Decision,
This decision was based on the Administrative Record, which has been developed in accordance
with Section 113(k) of CERCLA, and which is available for review at the Tewksbury Public
Library and at the United States Environmental Protection Agency (EPA) Region 1 OSRR
Records Center in Boston, Massachusetts. The Administrative Record Index (Appendix E to the
ROD) identifies each of the items comprising the Administrative Record upon which the
selection of the remedial action is based.
The Massachusetts Department of Environmental Protection, as representative for the
Commonwealth of Massachusetts, concurs with the Selected Remedy.
B. ASSESSMENT OF THE SITE
The response action selected in this ROD is necessary to protect the public health or welfare or
the environment from actual or threatened releases of hazardous substances into the
environment.
C. DESCRIPTION OF THE SELECTED REMEDY
This ROD sets forth the selected remedy for the Sutton Brook Disposal Area Site, which
involves the treatment of contaminated groundwater, the containment of groundwater, the
excavation and containment of contaminated soils and sediments, and the containment of landfill
waste, to prevent risks to potential future residents and facility workers and to protect terrestrial
and aquatic wildlife. The remedy also requires institutional controls to prevent exposure to
contaminated media prior to cleanup levels being achieved as well as to protect constructed
components of the remedy. The selected remedy is a comprehensive approach for this Site that
addresses all current and potential future risks caused by soil, groundwater, surface water and
sediment contamination. Specifically, this remedial action addresses contaminated soils in the
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Part 1: The Declaration
Garage and Storage Area and the Former Drum Disposal Area, contaminated groundwater
throughout the Site outside of the landfill lobes, and surface water and sediments in Sutton Brook
directly between the landfill lobes. The remedial measures will ensure that; groundwater
throughout the Site will no longer present an unacceptable risk to future residents or future
facility workers via ingestion or inhalation and will be suitable for consumption; the soils at the
Site (Garage and Storage Area) will no longer present an unacceptable risk to future residents via
direct contact and will be suitable for unrestricted use; presumed risk from contact with landfill
waste will be eliminated; soils at the Site (Former Drum Disposal Area) will no longer be a
source of groundwater contamination; ongoing impacts to groundwater from landfill waste, will
be reduced or eliminated; and restoration of impacted brook sediments and surface water will
provide protection of ecological receptors.
The major components of this remedy are:
- Excavation of contaminated soils and sediments above site specific cleanup levels (soils
at the Garage and Storage Area and the Former Drum Disposal Area, and
contaminated sediments from Sutton Brook between the landfill lobes);
- Consolidation of excavated soils, sediments, and debris into the landfill;
Construction of a multi-layer impermeable cap over the landfill lobes;
- Interception of groundwater from the southern lobe;
- A combination of collection and treatment and monitored natural attenuation for
contaminated groundwater;
- Institutional controls; and
Long-term monitoring.
This is a comprehensive remedy. There are no Operable Units at this Site.
The selected response action addresses principal and low-level threat wastes at the Site by:
treating and containing groundwater to address principal threat wastes; containing landfill waste
to address principal threat wastes; and excavating and containing contaminated soils and
sediments to address principal and low-level threat wastes.
D. STATUTORY DETERMINATIONS
The selected remedy is protective of human health and the environment, complies with Federal
and State requirements that are applicable or relevant and appropriate to the remedial action
(unless justified by a waiver), is cost-effective, and utilizes permanent solutions and alternative
treatment (or resource recovery) technologies to the maximum extent practicable.
This remedy also satisfies the statutory preference for treatment as a principal element of the
remedy (i.e., reduce the toxicity, mobility, or volume of materials comprising principal threats
through treatment).
Because this remedy will result in hazardous substances remaining on-site above levels that
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Part 1: The Declaration
allow for unlimited use and unrestricted exposure (and groundwater and/or land use restrictions
are necessary), a review will be conducted within five years after initiation of remedial action to
ensure that the remedy continues to provide adequate protection of human health and the
environment.
E. SPECIAL FINDINGS
Issuance of this ROD embodies specific determinations made by the Regional Administrator's
delegee, the Director of the Office of Site Remediation and Restoration, pursuant to CERCLA
and Section 404 of the Clean Water Act, 33 L'.S.C. § 1344, that the remedy is the least damaging
practicable alternative for protecting aquatic ecosystems at the Site under the standards of 40
C.F.R. Part 230. Specifically, at the landfill lobes, EPA expects impacts to both wetlands and the
100-year floodplain. At the landfill lobes, EPA proposes capping the waste in place, and
excavating contaminated sediments between the landfill lobes which will result in extensive
disturbances to these already impacted wetlands. The potential need for replacement floodplain
storage capacity will be addressed during the design process and alteration of wetlands will be
addressed through mitigation measures. Due to the proximity of the landfill lobes to this wetland
area, as well as the existing sediment contamination, and the need to provide the proper slopes
for the landfill cap, EPA cannot identify a less damaging practicable alternative for the remedy
which would avoid impacts to the aquatic environment while adequately addressing site risks.
F. ROD DATA CERTIFICATION CHECKLIST
The following information is included in the Decision Summary section of this Record of
Decision. Additional information can be found in the Administrative Record file for this Site.
1. Chemicals of concern (COCs) and their respective concentrations
2. Baseline risk represented by the COCs
3. Cleanup levels established for COCs and the basis for the levels
4. Current and future land and ground-water use assumptions used in the baseline risk
assessment and ROD
5. Land and groundwater use that will be available at the Site as a result of the selected
remedy
6. Estimated capital, operation and maintenance (O&M), and total present worth costs;
discount rate; and the number of years over which the remedy cost estimates are
projected
7. Decisive factor(s) that led to selecting the remedy
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Part 1; The Declaration
8. The selected response action addresses principal and low-level threat wastes at the Site
by: treating and containing groundwater to address principal threat wastes; containing
landfill waste to address principal threat wastes; and excavating and containing
contaminated soils and sediments to address principal and low-level threat wastes.
G. AUTHORIZING SIGNATURE
This ROD documents the selected remedy for soils, groundwater, surface water and sediments at
the Sutton Brook Disposal Area. This remedy was selected by EPA with concurrence of the
Massachusetts Department of Environmental Protection.
Concur and recommended for immediate implementation:
U.S. Environmental Protection Agency
By: Q Date: 1 '27 (T7
yffimes T Owens, III
director
Office of Site Remediation and Restoration
Region 1
Sutton Brook Disposal Area Superfuricl Site, Tewksbury, Massachusetts
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Part 2: The Decision Summary
A. SITE NAME, LOCATION AND BRIEF DESCRIPTION
Sutton Brook Disposal Area Superfund Site
South Street
Tewksbury, MA
CERCLIS Number: MAD980520696
US EPA is the lead agency
Sutton Brook Disposal Area is primarily a landfill
Site Description
The Sutton Brook Disposal Area, referred to during most of its history as the Rocco's Landfill or
Tewksbury Town Dump, is located on approximately 100 acres of land off South Street on the
eastern boundary of the Town of Tewksbury, Middlesex County, Massachusetts. A small
portion of the landfill also extends into the Town of Wilmington, Two major source areas exist
on the Site: the Landfill Lobes, which include the Northern Lobe and Southern Lobe; and the
Former Drum Disposal Area (FDDA). The Landfill Lobes comprise about 40 acres of the Site.
In 2000, between 300 and 400 buried drums were removed from the FDDA, which is located
outside the southwest edge of the Northern Lobe, Sutton Brook (and associated wetlands) flows
east to west through the property, Sutton Brook itself divides the landfill into the Northern and
Southern lobes. Additional wetland areas are located south of the landfill and along the eastern
and western portions of the property.
A more complete description of the Site can be found in Section I of the Remedial
Investigation Report (Woodard & Curran, 2007).
B, SITE HISTORY AND ENFORCEMENT ACTIVITIES
1. History of Site Activities
Waste disposal activities at the Site can be traced back to at least 1957, when the Town of
Tewksbury Board of Health designated the property as a dumping area. Until approximately
1988, the Rocco's Landfill (which is roughly synonymous with the Site) accepted municipal,
commercial, and industrial wastes from both inside and outside of the Town of Tewksbury,
including unknown quantities of hazardous substances.
A more detailed description of the Site history can be found in Section 1 of the Remedial
Investigation Report.
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2. History of Federal and State Investigations and Removal and Remedial Actions
The Site was proposed to the National Priorities List (NPL) in July of 2000, and the Site's NPL
listing was finalized in June of 2001. As discussed below and shown in the following table,
numerous investigations have taken place during the history of the Site,
In 1983, the Massachusetts Department of Environmental Protection (MassDEP) inspected the
landfill and took a number of samples of water from a brook within the boundaries of the Rocco
property. The MassDEP analysis showed the presence of organic compounds in the samples
taken on Rocco property downstream of the landfill, and it was determined that the cause of the
contamination was the groundwater from the landfill.
EPA issued a Site Inspection Report, on August 15, 1991, using available State and EPA file
information, interviews with local officials, and information gathered during on-site
reconnaissance and environmental sampling efforts. The Site Inspection Report identified the
need for continued investigation of the landfill to determine whether it could be eligible for
inclusion on the NPL.
As an interim measure, the Site was referred to the Removal Program for an assessment of the
public health concerns and the potential for a response action. Based on sampling and analysis
conducted by the Removal Program in 1992, coupled with the evaluation provided by the
Agency for Toxic Substances and Disease Registry (ATSDR), a determination was made that an
immediate health threat did not exist at that time, and a removal action was not warranted. The
MassDEP remained the lead agency for monitoring conditions at the Site.
In May of 1999, the MassDEP received information that drums had been buried at the landfill.
In response, the MassDEP conducted a magnetometer survey of areas outside the footprint of the
landfill for evidence of buried metal objects. A number of "magnetic anomalies" were detected
and a backhoe was used to dig test pits to see if the areas contained metal drums. Only one area
was found to contain drums. Approximately 60 crushed metal drums were discovered, with the
surrounding soils found to be contaminated with hazardous materials, including but not
necessarily limited to, toluene, xylene, and phthalates.
In early June 1999, the MassDEP installed groundwater monitoring wells near the area where the
crushed drums were discovered. Sampling results showed that groundwater in the vicinity where
the drums were found was contaminated with the same hazardous materials found in the
overlying soils.
At the request of the MassDEP, the EPA Removal Program conducted a preliminary
assessment/site investigation (PA/SI) to supplement information gather by the MassDEP from
July 26, 1999 through August 11,1999. EPA concluded that a removal action was warranted in
a Site Investigation Closure Memorandum dated August 10,1999.
Following mobilization of equipment and personnel and Site preparation activities, soil
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excavation began on July 20, 2000, Excavation of contaminated soils, drums, and containers
was completed on November 13,2000. As the soils were excavated, they were staged into two
stockpiles based on photoionization detector (PID) readings, visible observation, and on-site
screening for volatile organic compounds. The larger of the two piles was limited to soils,
Contaminated debris, visibly contaminated soils, and soils which registered higher
concentrations and/or PID readings were placed into the smaller of the two piles. Both piles
were secured with tarpaulins while transportation and disposal arrangements were finalized.
On December 18, 2000, four roll off boxes containing empty drums, drum parts, and used
personal protective equipment were shipped off-site for landfill disposal. Transportation of the
soils from the larger of the two piles for off-site treatment and disposal was also initiated on that
date. On February 19, 2001, the last four truckloads of soils from the larger pile were shipped
off-site for treatment and disposal. A total of approximately 10,000 tons of soils was shipped for
thermal desorption treatment and disposal.
On October 10, 2001, EPA issued a Unilateral Administrative Order (UAO) for removal. Under
this UAO, a group of PRPs completed the removal of the remaining contaminated soil pile at the
Site by February, 2002.
Date
Action
Who
Undertook
Results
Related
Documents
1989
Sampling
EPA
11 Soil Samples,
3 Sediment Samples
Report
1992
Air Sampling
EPA
7 Ambient Air Samples
Tech Memo
1996
Initial Site
Assessment
MassDEP
Landfill Gas Samples,
Groundwater Samples
Sediment Samples
Surface Water Samples
Report
1999
Preliminary
Assessment/
Site
Investigation
EPA
Soil Samples
Report
1999
Site
Investigation
Closure
Memo
EPA
Documented that a
Removal Action was
Warranted
Memorandum
2000
Preliminary
Data Report
Sampling
MassDEP
Groundwater and
Surface Water
Sampling
Report
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2000
Action Memo
EPA
Initiated Removal
Action
2000
Final Trip
Report
EPA
Groundwater, Soil,
Wetland Soil,
Sediment, and Surface
Water Samples
Report
2001
Preliminary
Assessment
EPA
Soil samples - Bemis
Circles
Report
2001
Data
Evaluation
EPA
Groundwater Sampling
Technical
Memorandum
2002
Completion
of Work
Report
EPA
Post-Excavation Soil
Samples
Documented
Completion of the
Removal Action
2002
Sampling
USGS
Passive Vapor
Diffusion and Surface
Water Samples
Report
2002
Sampling
Perkins
Development
Trust
Groundwater and Soil
Samples
Application for
Downgradient
Property Status
3. History of CERCLA Enforcement Activities
On April 18, 2000, July 27,2000 and June 22,2001, EPA notified 12 potentially responsible
parties ("PRPs") of their potentially liability at the Site. Responsible parties under CERCLA
include persons who are current or former owners and/or operators of a site, persons who
arranged for disposal of hazardous substances at a site (often called "generators"), or persons
who accepted hazardous substances for transport to a site selected by such persons (often called
"transporters"). On October 10, 2001, EPA issued a Unilateral Administrative Order (UAO) to
the 12 noticed PRPs to complete the removal action that was initiated by EPA in 2000. Eight
PRPs complied with the UAO to dispose of stockpiled contaminated soils at an off-site location.
On May 10,2002, EPA notified 31 additional PRPs of their potential liability at the Site, and in a
special notice letter, EPA invited the 43 noticed PRPs to participate in formal negotiations with
EPA to perform or finance the Remedial Investigation/Feasibility (RI/FS). On October 25, 2002,
EPA sent letters to four of the previously noticed PRPs conditionally withdrawing notice of
potential liability. In February 2004, EPA reached an agreement with 27 PRPs to conduct the
RI/FS at the Site with EPA oversight. These PRPs have been active in the remedy selection
process, having performed the RI/FS and submitting comments on the Proposed Plan during the
public comment period. On August 31, 2007, EPA notified 23 additional PRPs of their potential
liability at the Site
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C. COMMUNITY PARTICIPATION
Throughout the Site's history, community concern and involvement has been high. EPA has
kept the community and other interested parties apprised of Site activities through informational
meetings, fact sheets, press releases and public meetings. Below is a brief chronology of public
outreach efforts.
• On July 11, 2001, EPA held an informational meeting to discuss plans for the Site,
following the final listing of the Site on the National Priorities List (NPL).
• In the summer of 2002 EPA gathered information and conducted interviews with
representatives of the Town of Tewksbury and community members in order to develop
a Reuse Assessment for the Site. The Reuse Assessment was prepared September,
2002.
• In December 2002, the EPA released a community relations plan that outlined a
program to address community concerns and keep citizens informed about and involved
in remedial activities.
• On May 12,2004, EPA held an informational meeting to discuss the plans for the
RI/FS and the settlement with a group of PRPs to perform the RI/FS under EPA
oversight.
• On June 15, 2007, EPA published a notice and brief analysis of the Proposed Plan in
the Lowell Sun, and made the plan available to the public at the Tewksbury Public
Library located at 300 Chandler Street, Tewksbury, MA.
• On June 20, 2007 EPA made the administrative record available for public review at
EPA's offices in Boston and at the Tewksbury Public Library located at 300 Chandler
Street, Tewksbury, MA. This will be the primary information repository for local
residents and will be kept up to date by EPA.
• On June 27, 2007, EPA held an informational meeting to discuss the results of the
Remedial Investigation and the cleanup alternatives presented in the Feasibility Study
and to present the Agency's Proposed Plan to a broader community audience than those
that had already been involved at the Site. At this meeting, representatives from EPA
and the PRPs answered questions from the public.
• From June 28 to July 28, 2007, the Agency held a 30 day public comment period to
accept public comments on the alternatives presented in the Feasibility Study and the
Proposed Plan and on any other documents previously released to the public.
• On July 18, 2007, the Agency held a public hearing to discuss the Proposed Plan and to
accept any oral comments. A transcript of this meeting and the comments and the
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Agency's response to comments are included in the Responsiveness Summary, which is
part of this Record of Decision.
• Local residents formed an organization entitled T.O.X.I.C., Inc. to monitor Site
activities. They applied for a TAG grant on December 6, 2000. A grant was awarded
on February 15,2001. T.O.X.I.C., Inc has retained a TAG consultant who has attended
some technical project meetings and has reviewed and provided comments on draft
documents during the development of the Remedial Investigation/Feasibility Study.
D. SCOPE AND ROLE OF OPERABLE UNIT OR RESPONSE ACTION
The selected remedy was developed by combining components of different source control and
management of migration alternatives to obtain a comprehensive approach for Site remediation.
In summary, the remedy provides:
Excavation of contaminated soils and sediments above site specific cleanup levels;
Consolidation of excavated soils, sediments, and debris into the landfill;
Construction of a multi-layer impermeable cap over the Landfill Lobes;
Interception of groundwater from the Southern Lobe;
A combination of collection and treatment and monitored natural attenuation for
contaminated groundwater; and
Institutional controls, long-term operation, maintenance and monitoring.
The remedy addresses potential risks from contaminated soils, surface water, sediments and
groundwater,
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Part 2: The Decision Summary
The principal and low-level threats that this ROD addresses are summarized in the following
table:
Principal Threats
Affected Media
Contaminant(s)
Action To Be
Taken
Waste/Soils in Landfill
Lobes
(1)
Source Control
(Capping)
Indoor Air (FDDA) -
Vapor Intrusion
Originating from
Groundwater and Soil (3)
Contamination
Toluene,
Xylenes
Source
Removal
Groundwater
Aromatic VOCs,
Chlorinated VOCs,
Ketones,
1,4-Dioxanc,
Metals
Active
T reatment and
MNA
Surface Water (Upper
Sutton Brook - Site
Channel)
(2)
Source Control
Low Level Threats
Affected Media
Contaminant^)
Action To Be
Taken
Upland Soils (GSA)
PAHs
Source
Removal
Upland Soils (GSA)
Di-n-octylphthalate,
Metals
Source
Removal
Upland Soils (FDDA)
Aromatic VOCs,
Phthalates,
Naphthalene
Source
Removal
Sediments (Upper Sutton
Brook - Site Channel)
(2)
Source
Removal
Notes
(1) Presumptive remedy employed; specific risk-drivers have not been defined
(2) As part of the presumptive remedy, this medium/area has been presumed to have ecological risk, but
specific risk-drivers were only assumed based on screening-level evaluation and have therefore not been
included in the table. See Section G for further information,
(1) The contribution of soil VOCs to future indoor air impacts was not quantitatively assessed in the risk
assessment. However, the residual levels of contaminants in soils may present a principal threat for the
vapor intrusion pathway due to their high volatility.
E. SITE CHARACTERISTICS
Section 2.0 of the Feasibility Study (FS) Report contains an overview of the Remedial
Investigation. The significant findings of the Remedial Investigation are summarized below.
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Part 2: The Decision Summary
Refer to the Remedial Investigation (RI) Report for complete details.
1. Conceptual Site Model
The sources of contamination, release mechanisms, exposure pathways to receptors for the Site,
as well as other site-specific factors, are diagrammed in a Conceptual Site Model (CSM), which
is provided in attached Figure E-l. The CSM is a three-dimensional "picture" of site conditions
that illustrates contaminant sources, release mechanisms, exposure pathways, migration routes,
and potential human and ecological receptors. It documents current and potential future site
conditions and shows what is known about human and environmental exposure through
contaminant release and migration to potential receptors. The risk assessment and response
action for the Site are based on this CSM.
The sources of contamination for the Site are primarily the landfill waste, soils at the Former
Garage and Storage Area (GSA), and buried drums at the Former Drum Disposal Area (FDDA).
The primary constituents detected in the groundwater samples near the Landfill Lobes were
volatile organic compounds (VOCs) and metals followed by semi-volatile organic compounds
(SVOCs) in several wells and one pesticide. The highest concentrations of VOCs were detected
in the wells located adjacent to the northwestern and northeastern sides of the Southern Lobe.
The VOC generally detected at the highest concentration in the wells was toluene.
Similar constituents as detected in groundwater were also detected in surface water and sediment
samples. The samples with the highest concentrations were detected in the stretch of Sutton
Brook which traverses in between the two Landfill Lobes.
A removal action was conducted in the FDDA, initially performed by EPA in 2000 and
completed by a group of PRPs in 2002, in which approximately 300 to 400 crushed drums were
excavated and 13,786 tons of soils were transported off-site for disposal at an approved facility.
Post-excavation data indicated that residual levels of VOCs (benzene, TCE, toluene, PCE,
ethylbenzene, trimethylbenzenes, and xylenes) and SVOCs (bis(2-ethylhexyl)phthalate, di-n-
oetylphthalate, and naphthalene) are present in soils. The highest concentrations of VOCs and
SVOCs were detected at or just above the water table surface (4 to 6 feet below current grade)
and decrease with depth. The highest total VOC and SVOC concentrations were detected in
samples located on the southeast portion of the FDDA, Approximately 9,000 cubic yards of
residually-impacted soils are estimated to remain in this area.
The primary migration pathways for these residual contaminants are infiltration/leaching into the
subsurface with subsequent transport via groundwater flow. In addition, soil erosion and volatile
air emissions are potential migration pathways for contaminants that may be exposed or migrate
to the surface. However, the highest concentrations of contaminants are not located at the
ground surface.
VOCs were also the primary constituents detected in the groundwater samples at the FDDA with
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benzene, toluene, ethylbenzene, and xylenes (BTEX) and lower concentrations of 1,1,1 -TC A,
TCE, and 1,1-DCA being detected at the greatest frequency. Elevated concentrations of 4-
methyl-2 pentanone, 2-butanone, and phenols were also detected in groundwater proximate to
the FDDA.
These data indicate that there are two primary contaminant plumes in groundwater beneath the
Site. The sources of these plumes are the FDDA and the Southern Lobe (the Northern Lobe
contributes a relatively small amount of groundwater contamination when compared with the
FDDA and the Southern Lobe). As contaminants within these plumes migrate away from the
source areas, the plumes discharge into the wetland area and Sutton Brook. The results of the
surface water and sediment sampling within the brook and wetland areas correlate well with
groundwater contamination and groundwater plume discharge areas.
2. Site Overview
The Sutton Brook Disposal Area, also referred to as Rocco's Landfill, is located off South Street
on the eastern boundary of the Town of Tewksbury, Middlesex County, Massachusetts. A small
portion of the Site also extends into the Town of Wilmington. Key site features and ground
surface contours are illustrated on attached Figure E-2. For purposes of presentation and
discussion, the Site is divided into the following two major source areas: the Landfill Lobes,
referred to as the Northern Lobe and Southern Lobe, and the FDDA. The solid waste source
areas comprise about 40 acres of the Site. In 2000, between 300 and 400 buried drums were
removed from the FDDA, which is located northwest of the Northern Lobe. Sutton Brook (and
associated wetlands) flows east to west through the property, dividing the landfill into the
Northern and Southern lobes. Additional wetland areas are located south of the landfill and
along the eastern and western portions of the Site.
The majority of the Site is unpaved and relatively flat, aside from the steeply-sloped landfill
lobes. Outside the landfill lobes, the Site primarily consists of wetlands including several
individual wetland areas (a red maple swamp/floodplain associated with Sutton Brook [greater
than 50 acres]; a small man-made pond (approximately 2 acres); man-made areas subject to
flooding (small forested wetland area and a borrow pit); and an emergent wetland area).
The overburden geology of the area is characterized by glacial features (e.g., outwash and till
deposits). The site-specific unconsolidated materials underlying these surficial deposits consist
primarily of sand layers (stratified drift) underlain by a till laid down on top of bedrock. Depth
to rock at the Site ranges from 20 to 60 feet below ground surface (ft bgs). The mapped rock,
along with the rock cores obtained during the RI, indicate that two types of rock were
encountered beneath the Site. A granite or granodiorite, referred to as the Andover Granite, is
classified as a light to medium-gray, foliated, medium to coarse grained muscovite-biotite
granite. The other rock type, gneiss, is classified as a thinly bedded to massive amphibolite;
minor biotite gneiss. A weathered zone was observed at the top of the rock followed by more
competent rock with moderate fracturing.
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Unlike the ground surface topography (aside from the landfills), the bedrock surface topography
varies considerably across the Site. A bedrock outcrop was observed on the westernmost portion
of the area adjacent to Sutton Brook. The bedrock surface generally slopes in a southerly to
southwesterly direction across the Site. A deep bedrock valley on the southwestern portion of
the Site has been filled with glacial drift deposits creating a higher transmissivity water zone
(e.g., the Town's former Poplar Street wellfield was located in this valley).
The ground surface across the Site consists of landfill lobes or fill areas, wetland soils, or an
upper sand layer. The upper sand layer (10 to 45 feet in thickness) is comprised of a brown to
gray medium to fine sand with a little silt and exists across the entire Site. The units underlying
this layer are controlled by the depth to bedrock and the presence and thickness of a till layer. In
areas of deeper bedrock, coarser sand with some gravel was encountered beneath this upper sand,
as seen on the western portion of the Site.
The main hydrologic feature at the Site is Sutton Brook and associated tributaries and wetlands.
Sutton Brook is a medium gradient stream that includes both moderately moving water through
established banks and slower moving water through much wider and less-established channels.
The stream bed is comprised of sand and gravel with some areas of muck and peat. Sutton
Brook originates in an upland area north of the Site in Andover and flows southerly, turning
westerly to northerly through the Site with discharge to the Shawsheen River approximately
2,500 feet northwest of South Street. As Sutton Brook traverses the Site, the character of the
brook is affected by the channel width, the channel depth, the composition of the soils
underlying the brook, and tributaries that contribute to the brook.
Based on the majority of the water table elevations, surface water elevations, and stream gauging
measurements, EPA has concluded that shallow groundwater generally discharges to Sutton
Brook. In contrast, the wetlands area and smaller tributaries experience variable elevations,
indicating that they both discharge to and are recharged by shallow groundwater throughout the
seasons.
Depth to groundwater at the Site ranges from approximately near/at ground surface to a depth of
approximately 12 feet below ground surface. In general, the water table surface (i.e., top of the
groundwater surface) mimics the natural land surface topography of the area and is influenced by
the streams and wetland areas. Generally, the overall groundwater flow patterns are similar
throughout the seasons: north of the Site, groundwater flows southerly towards Sutton Brook or
westerly towards the Shawsheen River; groundwater east of the Site flows westerly or southerly
towards Sutton Brook and an unnamed tributary; groundwater south of the Site flows northerly
towards Sutton Brook or the Shawsheen River; and groundwater west of the Site flows either
northerly toward the Shawsheen River or easterly towards Sutton Brook. Groundwater in the
intermediate overburden also flows toward Sutton Brook and the Shawsheen River.
Due to the changes in water levels, slight changes in the direction of groundwater flow were
observed from the groundwater low measurements (September 2005) to the groundwater high
measurements (May 2006), specifically on the northwest portion of the Site near the FDDA and
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in the wetland area south of Sutton Brook. Still, under both seasons, flow continued towards
Sutton Brook and eventually followed the direction of the stream flow of Sutton Brook. The
FDDA also exhibited the flattest horizontal gradients at both the water table surface and the
intermediate overburden potentiomctric surfaces. There were similar, slight localized changes in
the groundwater flow patterns on other areas of the Site from season to season. However,
overall, groundwater flow at the Site measured over the seasons remains consistent with the
regional groundwater flow patterns. (See Attached Figure E-3)
Based on a review of the hydraulic gradients, groundwater flow is in a predominantly horizontal
direction (horizontal gradients greater than vertical gradients) with an upward flow component
under the majority of conditions. This average upward flow pattern is maintained through the
seasonal variations measured at the Site.
3. Remedial Investigation Sampling Strategy
Data collected at the Site and surrounding areas and used in the Remedial Investigation are
comprised of both previous Site investigations and the recently completed Phase 1A and Phase
IB Remedial Investigations. These data encompass sampling and investigation activities
performed from 1989 to 2006 (together referred to as the Rl).
The recent RI field activities (i.e., 2004 and 2006) consisted of activities related to the following
tasks:
• Site Survey (elevation and location surveys of investigation points)
• Soils and Sources of Contaminants Investigation (soil borings, surficial soil sampling,
and test pit excavations)
• Subsurface and Hydrogeological Investigation (installation of temporary and permanent
monitoring wells, groundwater sampling, stream piezometer installation, water level
measurements, stream gauging, in situ hydraulic conductivity testing, and groundwater
modeling)
• Air Quality Assessment (landfill gas sampling)
• Surface Water and Sediment Investigation (surface water, wetland soil/sediment, and
sediment sampling)
• Ecological Assessment (wetland delineation, floodplain delineation, and habitat
characterization)
Samples were analyzed by the off-site laboratory for VOCs, SVOCs, metals, PCBs, pesticides,
and general chemistry parameters. A summary of the combined data set developed as part of this
RI, which includes previous data deemed "usable" through the data review process and the
recently collected data, is provided in the table below.
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Summary of Rl Locations
Sample Media
Total Number of
Locations -
Previous
Investigations
Total Number of
Locations -
Phase 1 ARMB Rl,
and pre-ROD
(2004-2006)
Total Number of
Locations
Test Pit Explorations
10
38
48
Soil Samples (Surface, Wetland,
and Sub-Surface)
55
41
96
Monitoring Wells, including
Temporary Wells and
Piezometers
64
46
110
Groundwater Sampling Events1
4
8
12
Landfill Gas
3
8
11
Sediments
27
45
72
Surface Water
16
28
44
Ambient Air
7
0
7
Leachate
0
2
2
Notes;1 Not all monitoring wells were sampled during each sampling event.
Following analysis, data usability was assessed by reviewing laboratory data for each medium
and assessing whether they met the prescribed project quality objectives (PQOs) developed in
the Quality Assurance Project Plan (QAPP). These data were reviewed in terms of their
precision, accuracy, representativeness, completeness, and comparability (PARCC). The historic
data deemed "usable" (see above) were determined to be generally consistent with QAPP
requirements and suitable for use in the Rl.
Based on the results of the data quality assessment, data collected during the Rl are considered to
be suitable for their intended use in satisfying the Rl objectives. These objectives (or end uses)
include evaluating the contaminant sources; determining the nature, extent, and distribution of
contaminants; and assessing the current and future potential risks to human health and the
environment,
4. Nature and Extent of Contamination
For discussion purposes, the nature and extent of contaminants at the Site have been divided into
the following areas:
• Source Areas
o Landfill Lobes
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o Former Drum Disposal Area
o Garage, and Storage Area
• Non-Source Areas - wetlands, brook and downgradient groundwater
A summary of the principal RI findings for each of these source areas is presented in the
following sections.
Landfill Lobes
Of the two Landfill Lobes, the Northern Lobe is the largest at approximately 30 acres (estimated
1.9 million cubic yards of material) whereas the Southern Lobe comprises approximately 10
acres (estimated 0.3 million cubic yards of material). Small debris/waste piles have also been
identified in five distinct areas near the Landfill Lobes. The Landfill Lobes constitute the
primary source areas at the Site. A depiction of the Landfill Lobes is presented on Attached
Figure E-4.
The primary migration pathways for contaminants from the Landfill Lobes are:
• infiltration/leaching of contaminants from the waste into the subsurface with subsequent
transport via groundwater flow;
• soil erosion and wind blown transport of contaminants that are exposed at the surface,
including both dust and surface water runoff; and
• volatile air emissions and transport.
Landfill gases generated from the two lobes ranged from 14 to 70% methane; 15 to 34% carbon
dioxide; and 0.7 to 540 ppm total VOCs. The VOCs detected at the greatest frequency in the
landfill gas samples were toluene, xylene, ethylbenzene, n-hcxane, and dichlorofluoromethane.
Based on the RI data (visual observations of the slopes; groundwater samples proximate to the
lobes; surface water and sediment samples; and landfill gas and ambient air samples),
groundwater migration is the primary contaminant migration pathway associated with the lobes
for the following reasons: 1) the uncapped/uncontained nature of the landfill does not limit
infiltration and subsequent leaching; 2) wastes are most likely located at or near the water table
surface; 3) the presence of VOCs in Sutton Brook in-between the Landfill Lobes; 4) typical
landfill gas levels in the subsurface and low to non-detect concentrations of VOCs in ambient air
indicating minimal mass transport; and 5) the majority of the material in the lobes is covered on
the ground surface with soils and/or vegetation, thereby reducing transport by runoff.
The primary constituents detected in groundwater samples were VOCs and metals. The highest
concentrations of VOCs were detected in the groundwater collected from monitoring wells
located adjacent to the northern sides of the Southern Lobe. Total VOC concentrations in these
wells ranged from 3,450 to 57,210 ug/l (2004 data). The VOC generally detected at the highest
concentration in the wells was toluene. Groundwater data from the wells along the perimeter of
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the Northern Lobe were much lower in concentration (total VOCs ranged from 53 to 842 ug/1 -
2004 data). Unlike the Southern Lobe, the VOC generally detected at the highest concentration
in the wells near the Northern Lobe was either 1,4-dioxane or tetrahydrofuran. Based on
information collected during the RI» the Southern Lobe appears to be the primary contributor to
the elevated concentrations of volatile organics in groundwater and in Sutton Brook sediments.
The overall distribution of total VOCs in groundwater supports groundwater flow in the direction
of Sutton Brook, Similar constituents to those detected in groundwater were also detected in
leachate samples and in surface water and sediment samples. Surface water and sediment
samples with the highest concentrations were detected in the stretch of Sutton Brook between the
two lobes. A depiction of this area along with the approximate limits of solid waste is depicted
on attached Figure E-4,
Former Drum Disposal Area
A removal action was conducted in this area, initially performed by EPA in 2000 and completed
by a group of PRPs in 2002, in which approximately 300 to 400 crushed drums were excavated
and 13,786 tons of soils was transported off-site for disposal (as non-hazardous waste). Post-
excavation data indicate that residual levels of VOCs (TCE, toluene, PCE, ethylbenzene,
trimcthy J benzenes, and xylenes) are present in soils, with toluene, ethylbenzene, and xylenes
exhibiting the highest concentrations and greatest frequency of detection. The highest total VOC
concentrations were detected in samples located on the southeast portion of the FDDA. This
area (southeast portion) also corresponds to an area of elevated SVOCs, specifically bis(2-
ethylhexyl)phthalate, di-n-oetylphthalate, and naphthalene, and the area where more of the drums
were formerly located. A depiction of the impacted soil area is presented on attached Figure E-5.
Similar to the contamination in soils, VOCs were the primary constituents detected in the
groundwater samples at the FDDA, with benzene, toluene, ethylbenzene and xylenes, and lower
concentrations of 1,1,1-TCA, TCE, and 1,1-DCA being detected at the greatest frequency.
Elevated concentrations of 4-methyl-2 pentanone, 2-butanone, and phenols were also detected in
groundwater proximate to the FDDA.
The dissolved VOC concentrations in groundwater were found to decrease with distance from
the FDDA. The highest concentrations of VOCs are located at an intermediate depth within the
overburden aquifer and within a low hydraulic conductivity medium to fine sand layer. The
groundwater data also indicate that impacts are limited to the overburden and that contaminants
have not migrated into the bedrock aquifer.
As the groundwater plume approaches Sutton Brook, the groundwater flow patterns and the
presence of conditions supporting natural degradation appear to be the controlling factors to the
nature and extent of the groundwater contamination in this area. Local groundwater (to the
immediate sides of the brook and in the wetland areas) flows east or west, respectively, towards
the brook and wetlands. There is also a net northerly component of flow (regional flow path)
that parallels the flow of the brook. The horizontal hydraulic gradients are relatively flat.
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especially in the intermediate overburden (area of higher groundwater contamination) as
groundwater approaches the wetlands/brook. These low gradients and low hydraulic
conductivity result in a reduced groundwater velocity and reduced subsequent contaminant
migration rates.
Historical contaminant analytical data and the existing subsurface geochemistry indicate that a
combination of natural attenuation processes (biodegradation, dispersion, dilution, adsorption,
volatilization, and/or chemical or biological stabilization, transformation, or destruction of
contaminants) are reducing contaminant concentrations and preventing continued downgradient
migration. The combination of hydrological conditions and natural degradation factors has
resulted in a stable plume configuration, and the contaminated plume is not expected to migrate
beyond its current configuration. Refer to the February 2007 RI Report and information
presented later in this section for further discussion on natural attenuation at the Site,
Garage and Storage Area
This area is located on the northwest portion of the Site and consists of the former residence,
garage, and storage areas (see attached Figure E-6). The majority of the area contains surfieial
debris from past and current storage activities. Impacted soils (petroleum hydrocarbons, PAHs,
and metals) are present on the south central portion of the area and most likely were caused by
storage or operation activities in this area. A subsurface fill area, comprised of wood, metal, and
concrete, is present on the southern portion of the area. Groundwater is not impacted from
operations within this area.
Non-Source Areas
The "non-source" areas primarily consist of the wetlands in areas away from the source areas
(i.e., hydraulically downgradient areas, upstream areas of Sutton Brook, and the nearby
tributaries). These areas and samples collected within these areas are shown on attached Figure
E-7.
The non-source areas also include the area of groundwater located hydraulically downgradient of
the "source areas" with organic constituents detected in excess of Federal drinking water
maximum contaminant levels (MCLs) (see attached Figure E-8). A combination of natural
attenuation processes (biodegradation, dispersion, dilution, adsorption, volatilization, and/or
chemical or biological stabilization, transformation, or destruction of contaminants) and
hydrogeological conditions are reducing contaminant concentrations in this "downgradient" area,
reducing the overall contaminant mass, and preventing contaminant migration beyond the current
configuration of the plume. This conclusion was based on the decreasing and/or stabilizing
groundwater plume, the presence of breakdown products, the reducing levels of electron
acceptors, and the increasing levels of metabolic by-products (i.e., ferrous iron and methane)
across the Site, Refer to the February 2007 RI Report and information presented later in this
section for further discussion on natural attenuation at the Site.
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In contrast, unlike the dissolved VOC plumes, arsenic concentrations in groundwater in excess of
MCLs are detected in wells on the Site and upgradient wells, suggesting that arsenic
concentrations may be naturally-occurring at "elevated" levels. Arsenic is a common
contaminant of concern at many landfills and the precise origin of the arsenic in groundwater is
often difficult to determine. A review of the analytical data indicates that arsenic levels have
remained fairly consistent over time with a slight upward pattern in select areas.
Higher concentrations of arsenic are found in areas adjacent to or immediately downgradient of
the Site source areas (landfill and FDDA). This condition appears to be related to the subsurface
environment and resulting geochemical processes caused by these source areas (e.g., reducing
conditions causing increased arsenic concentrations). As oxidizing conditions return to the
subsurface at locations away from these areas, the arsenic concentration in groundwater
decreases.
These conditions demonstrate that although some mass of arsenic may be a result of deposition
into the source areas, the resulting geochemistry within the subsurface has likely played a
significant role in the elevated arsenic levels immediately downgradient of the source areas.
Further discussion of arsenic in groundwater at this Site is provided in the February 2007 RI
Report.
5. Contaminant Fate & Transport
The following text provides insight as to the fate and transport of contaminants at the Sutton
Brook Disposal Area Site. For potential human and ecological exposure pathways, refer to the
Conceptual Site Model (Figure E-l).
Plume Characterization and Migration Pathways - VOCs
A depiction of the approximate areal extent of the primary constituents detected in groundwater
was presented in attached Figures E-9 through E-l 2. These figures depict the Southern Lobe and
the FDDA as the primary source areas for the VOC contaminant plumes. The purgeable
aromatic hydrocarbons and tetrahydrofuran plumes are similar in configuration, whereas the 1,4-
dioxane plume is more widespread, detected at lesser concentrations, and suggests source
contribution from both landfill lobes. These findings may be attributable to 1,4-dioxane being
more soluble and less degradable than the aromatic hydrocarbons.
The predominant factors that ultimately control the migration pathways of the contaminant
plumes include the hydrogeologic environment, the location and characteristics of the source
areas, and the partitioning/migration characteristics of the specific contaminants comprising the
plume. Based on the previous discussion on source characterization, fate and transport
characteristics of the predominant contaminants, and the site-specific hydrogeologic
environment, the processes of advection, dispersion, and natural degradation/attenuation are
most likely the primary characteristics controlling the migration of the dissolved VOC plumes in
groundwater. Figures E-9 through E-l2 also show that the plumes are generally contained
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within the immediate boundaries of the Site (i.e., plume configurations are controlled by
groundwater flow, discharge to the brook and associated wetlands, and degradation/attenuation
mechanisms).
As groundwater flows through the source areas, VOCs partition into the groundwater and flow
with groundwater away from the source areas, forming a dissolved VOC plume. The
predominant mechanism for migration of the plume away from the source area is through
advection (which refers to transport in a fluid, groundwater, in this case). In the area of the
Southern Lobe, it appears that groundwater (based on potentiometric head data) and the
dissolved VOCs (based on concentrations detected in monitoring wells) migrate away from the
source area in a predominantly northeasterly to northerly direction. In the area of the FDDA, the
dissolved VOCs migrate in a southwesterly to westerly direction towards Sutton Brook and the
associated wetlands.
Once both plumes reach the general vicinity of the brook and wetlands, the plumes merge with
regional groundwater flow and travel in a predominantly northerly direction. Based on hydraulic
gradients, the dissolved VOC plume predominantly migrates in the horizontal direction with a
slight upward component of flow as the plume approaches the brook and wetlands.
To aid in estimating the rate of contaminant movement, the numerical groundwater model
MODFLOW was used to simulate hydrogeologic conditions and the movement of groundwater
in the vicinity of the Site. Given that advection is the primary transport mechanism for the
dissolved VOC plume, the model was a useful tool to aid in the understanding of potential
contaminant migration pathways. The results of the model-simulated groundwater flow
directions were generally consistent with groundwater flow directions configured from the
groundwater level measurements. Based on the particle tracking analysis performed as part of
the model calibration, the simulated discharge locations for particles placed in the source areas
were consistent with actual mapped contaminant locations.
The higher VOC concentrations are detected in the intermediate overburden. Hydraulic
gradients in this zone of the aquifer are relatively flat (0.001 ft/ft range) and, when combined
with low conductivity, result in a reduced groundwater velocity and subsequent reduced
contamination migration rates. As such, contaminant dissolution, flushing, and dispersion
processes are expected to occur fairly slowly.
The groundwater data also indicate that contamination is limited to the overburden and has not
migrated into the bedrock aquifer. The bedrock wells installed downgradient of the source areas
(MW-7R, MW-8R, MW-22R, and MW-17B) were either non-detect for VOCs or detected low
concentrations (less than 2 ug/1). Several of these wells are located within the bedrock low or
"trough" downgradient of the source areas. Based on the location of these wells and the low
concentrations of VOCs detected, it is not likely that a non-aqueous phase would be present in
bedrock in this low area.
In summary, both the potentiometric surveys and the groundwater model confirm that dissolved
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VOCs and SVOCs (including purgeable aromatics, chlorinated compounds, and ketones, among
others) migrate away from the two main source areas and toward Sutton Brook and the wetland
areas surrounding Sutton Brook. Once at the brook and in the area of the wetlands surrounding
the brook (downgradient from both source areas), regional groundwater controls the flow regime
with groundwater following the brook, in a predominantly northerly flow direction.
Though the dissolved VOC plume predominantly migrates in the horizontal direction, hydraulic
data collected at the Site show that there is also a slight upward component of flow as the plume
approaches the brook/wetlands. Along with the low hydraulic conductivity and reduced
groundwater velocity estimated in the intermediate overburden, the upward component of flow
may also have an impact on contaminant transport at the Site since the potential for off-site
groundwater transport is further reduced. Because the upward component of flow will tend to
limit contaminant migration to bedrock, groundwater will be more likely discharge to surface
water.
Natural Attenuation Processes
Analytical and geochemical data have indicated that natural attenuation processes are occurring
within and downgradient of the source areas. These natural in-situ attenuation processes include
biodegradation, dispersion, dilution, adsorption, volatilization, and chemical or biological
stabilization, transformation, or destruction of contaminants. In addition, chemical footprint
indicators, including the absence of electron acceptors oxygen, nitrate, and sulfate and the
presence (and subsequent increase spatially on-site) of metabolic by-products methane and
ferrous iron have been measured within and immediately downgradient of source areas on-site,
indicating that biodegradation processes are interacting with contaminants in groundwater.
Contaminant Trend
No significant increasing trends in concentrations of dissolved VOCs or significant changes in
the shape of the dissolved VOC plumes have been detected at the Site throughout the sampling
events. Although a significant amount of new groundwater data have been recently collected,
the extent and concentration distribution of the plume on the Site appears to be generally
consistent throughout the past twelve years of sampling (dating back to 1995).
6, Principal and Low-Level Threats
Principal threat wastes are those source materials considered to be highly toxic or highly mobile
which generally cannot be contained in a reliable manner or would present a significant risk to
human health or the environment should exposure occur. The manner in which principal threats
are addressed generally will determine whether the statutory preference for treatment as a
principal element is satisfied. Wastes generally considered to be principal threats are liquid,
mobile, and/or highly-toxic source material.
Low-level threat wastes are those source materials that generally can be reliably contained and
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that would present only a low risk in the event of exposure. Wastes generally considered to be
low-level threat wastes include non-mobile contaminated source material of low-to-moderate
toxicity, surface soils containing chemicals of concern that are relatively immobile in air or
groundwater, low leachability contaminants, or low toxicity source material.
The principal and low-level threats that this ROD addresses are summarized in the following
table:
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Table E-l
Principal and Low-Level Threats
Principal Threats
Affected Media
Contaminant(s)
Reason(s)
Concentration(s)
Receptors
Waste/Soils in Landfill
Lobes
(1)
(1)
(1)
Human/
Ecological
Indoor Air (FDDA) -
Vapor Intrusion
Originating from
Groundwater and Soil (3)
Contamination
Toluene,
Xylenes
High Volatility
78 rng/L (Toluene),
28 mg/L (Xylenes)
Future
Resident;
Future Facility
Worker
Groundwater
Aromatic VOCs,
Chlorinated VOCs,
Ketones,
1,4-Dioxane,
Metals
High Mobility or
High Toxicity
115 rng/L (BTEX),
6.3 mg/L (Chlorinated
VOCs),
340 mg/L (Ketones),
3 mg/L (1,4-Dioxane),
2.3 mg/L (Arsenic)
Future
Resident;
Future Facility
Worker
Surface Water (Upper
Sutton Brook - Site
Channel)
(2)
(2)
(2)
Fish and
Invertebrate
Communities
Low Level Threats
Affected Media
Contaminants)
Reason(s)
Concentration^)
Receptors
Upland Soils (GSA)
PAHs
Low Volatility
and Leachability
130 mg/kg (Total
PAHs)
Future
Resident
Upland Soils (GSA)
Di-n-
octylphthalate,
Metals
Low Toxicity
Non-mobile
233 mg/kg (Lead),
379 mg/kg (Zinc)
Carnivorous
Wildlife;
Invertebrates
Upland Soils (FDDA)
Aromatic VOCs,
Phthalates,
Naphthalene
Low Toxicity
46 mg/kg (Aromatic
VOCs),
159 mg/kg
(Phthalates),
1,4 mg/kg
(Naphthalene)
Carnivorous
Wildlife;
Plants;
Invertebrates
Sediments (Upper Sutton
Brook - Site Channel)
(2)
(2)
(2)
Benthic
Invertebrates
Notes
(1) Presumptive remedy employed; specific risk-drivers have not been defined
(2) As part of the presumptive remedy, this medium/area has been presumed to have ecological risk; risk-
drivers were identified based on screening-level. See Section G for further information.
(3) The contribution of soil VOCs to future indoor air impacts was not quantitatively assessed in the risk
assessment. However, the residual levels of contaminants in soils may present a principal threat for the
vapor intrusion pathway due to their high volatility.
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F. CURRENT AND POTENTIAL FUTURE SITE AND RESOURCE USES
1. Land Uses
The Sutton Brook Disposal Area Site is essentially undeveloped and surrounded primarily by
open space, farming operations, a composting operation, and residential dwellings. An
unoccupied residential home (the former Roeco residence) is situated on the northwest corner of
the Site. The nearest occupied residences abut the Site boundary and are located on South Street
to the northwest, Bemis Circle and Serenity Drive to the west, and Carlton Road Extension and
Homestead Lane to the south. Freshwater wetlands are located south of the landfill and along
the eastern and western portions of the Site. The area within one-half mile of the Site is
primarily used for residential, light commercial/industrial, and agricultural purposes with areas
of protected open space present for recreational use.
As a practical matter, residential or other uses that require the construction of buildings and other
significant structures within the landfill lobes would be limited due to institutional controls that
will be placed to protect the remedy. Future recreational use of the wetland areas adjacent to the
landfill lobes would be compatible with Site controls and surrounding land uses. For the upland
areas adjacent to the landfill (the former drum disposal area and former residence, garage and
storage area), future reuse options may include both residential and commercial/industrial
development, possibly with family and/or group daycare centers.
A reuse assessment was performed for the Site in 2002. In part, development of the reuse
assessment involved interviews with town representatives and residents. Ideas relating to site
reuse ranged from a passive open conservation area to active recreational use such as athletic
fields, a golf course, driving range, or outdoor amphitheater. Tewksbury residents and local
organizations have also expressed a need for athletic fields. Based on the information provided
by the community representatives, residents favor reusing the Site as some form of open space,
possibly with recreational trails.
Reasonably anticipated future uses of the Site include passive recreational use of the wetland
areas and residential/commercial use of the upland areas, beyond the landfill lobes. Reasonably-
anticipated future uses of adjacent land in surrounding areas include recreational and
residential/commercial use.
The ultimate development of parcels adjacent to the Site has the potential to influence the nature
of the future ecological or recreational reuse on the Site itself. One particularly important parcel
is the Perkins Development Trust property, located northeast of the Site, across the abandoned
Boston and Maine railroad grade (see Figure E-2). This property has been the subject of a
number of development proposals, most recently a large shopping mall. It is possible that a new
exit may be built off of 1-93 to serve the development as well as other nearby properties in
Wilmington and Andover.
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2. Groundwater/Surface Water Uses
Within the vicinity of the Site are mapped medium and high yield potentially productive aquifers
and approved Zone 2 water supply areas. Several private wells are located in the nearby
residential areas. The Town of Tewksbury currently relies on the Merrimack River as its source
of drinking water (though not all residences are connected to the Town's system). However, the
Town has five inactive public water supply wells located southwest of the Site which were
abandoned in place around the mid 1990's (not due to impact from the Site).
Mass DEP completed a Groundwater Use and Value Determination for the Site in 1991
(Appendix B), The Department's recommendation supports a "medium" use and value, as the
aquifer under the Site is considered a medium yield aquifer and it is considered a potential
drinking water source. The potential beneficial use of the groundwater at the Site and
surrounding areas is use of the aquifer as a drinking water supply. There is no schedule currently
in place for this aquifer to be used as a drinking water supply.
The current and potential future use of the surface water at the Site and surrounding areas is
passive recreation. As no fish were found during fish surveys within Sutton Brook, fishing is not
considered as a potential future use.
G. SUMMARY OF SITE RISKS
A baseline risk assessment was performed to estimate the probability and magnitude of potential
adverse human health and environmental effects from exposure to contaminants associated with
the Site assuming no remedial action was taken. It provides the basis for taking action and
identifies the contaminants and exposure pathways that need to be addressed by the remedial
action. The baseline risk assessment followed a four step process: 1) hazard identification,
which identified those hazardous substances which, given the specifics of the Site were of
significant concern; 2) exposure assessment, which identified actual or potential exposure
pathways, characterized the potentially exposed populations, and determined the extent of
possible exposure; 3) toxicity assessment, which considered the types and magnitude of adverse
health effects associated with exposure to hazardous substances, and 4) risk characterization and
uncertainty analysis, which integrated the three earlier steps to summarize the potential and
actual risks posed by hazardous substances at the Site, including carcinogenic and non-
carcinogenic risks and a discussion of the uncertainty in the risk estimates. A summary of those
aspects of the human health risk assessment which support the need for remedial action is
discussed below, followed by a summary of the environmental risk assessment.
1. Human Health Risk Assessment
A baseline human health risk assessment (HHRA) was completed for the Sutton Brook Disposal
Area Site to evaluate the likelihood and magnitude of potential human health effects associated
with the Site. Due to different property uses, activities, and/or nature and extent of
contamination, the Site was divided into the following seven Groups (areas):
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• Groups 1 and 2 - Northern and Southern Landfill Lobes, respectively
• Group 3 - Former Drum Disposal Area and Adjacent Disturbed Area
• Group 4 - Former Residence, Garage and Storage Area
• Group 5 - Sutton Brook and Associated Tributary and Wetland Areas
• Group 6 - Area South of Southern Lobe
• Group 7 - Reference Locations
Consistent with EPA's Guidance on Presumptive Remedy for CERCLA Municipal Landfill
Sites, direct exposures at the Northern and Southern Landfill Lobes (Groups 1 and 2) were not
evaluated in the IIHRA due to the presumption that the two Landfill Lobes will be closed in-
place using current landfill capping technology. The HHRA evaluated the potential for
unacceptable risks to human receptors from exposure to contaminants in; ambient air emanating
from the landfill; upland soils at the former drum disposal area (FDDA; Group 3) and former
garage and storage area (GSA; Group 4); surface water, sediments, and wetland soils in Sutton
Brook and its associated wetlands (Group 5); sediments and surface water in the man-made pond
located south of the Southern landfill lobe (Group 6); groundwater beneath the Landfill Lobes
(Groups 1 and 2) and beyond the Landfill Lobes (Groups 3-6); and indoor and outdoor air
impacted via subsurface migration of volatile compounds at the FDDA and GSA.
Section 1: Identification of Chemicals of Concern
Eighty-six of the more than 100 chemicals detected at the Site were selected for evaluation in the
human health risk assessment as chemicals of potential concern. The chemicals of potential
concern were selected to represent potential site-related hazards based on toxicity, concentration,
frequency of detection, and mobility and persistence in the environment and can be found in
Tables 3-1 through 3-14 of the risk assessment (RI/FS Volume III, Woodard & Curran, 2007).
From this, a subset of the chemicals were identified in the FS as presenting a significant current
or future risk and are referred to as the chemicals of concern (COCs) in this ROD. The COCs
are identified in attached Tables G-l through G-4 for upland soils, indoor air, and groundwater
beneath (Groups 1 and 2) and beyond (Groups 3-6) the landfill lobes. These tables contain the
exposure point concentrations used to evaluate the reasonable maximum exposure (RME)
scenario in the baseline risk assessment for the chemicals of concern. Estimates of average or
central tendency exposure concentrations for the chemicals of concern and all chemicals of
potential concern can be found in Tables 3-23 through 3-30 of the baseline human health risk
assessment.
Section 2: Exposure Assessment
Current and potential future site-specific pathways of exposure to chemicals of concern were
determined. The extent, frequency, and duration of current or future potential exposures were
estimated for each pathway. From these, exposure parameters, a daily intake level for each site-
related chemical, was estimated.
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The Site is currently undeveloped and surrounded primarily by open space, farming operations, a
composting operation, and residential dwellings. Access to the Site is unrestricted, and there are
no currently occupied buildings present. The nearest occupied residences abut the Site boundary
and are located on South Street to the northwest, Bemis Circle and Serenity Drive to the west,
and Carlton Road Extension and Homestead Lane to the south. Sutton Brook flows from east to
west through the Site. Freshwater wetlands are located south of the landfill and along the eastern
and western portions of the Site. Within the vicinity of the Site are mapped medium and high
yield potentially productive aquifers and approved Zone 2 water supply areas. Several private
wells are located in the nearby residential areas. The Town of Tewksbury currently relies on the
Merrimack River as its source of drinking water. However, the Town has five inactive public
water supply wells located southwest of the Site which were abandoned in place around the mid
1990's.
The following is a brief summary of the exposure pathways that were found to present an
unacceptable risk at the Site. A more thorough description of all exposure pathways evaluated in
the risk assessment including estimates for an average exposure scenario, can be found in
Section 3,2 and on Tables 3-16 through 3-21 of the baseline human health risk assessment.
No current exposure pathways were found to present a significant risk at the Site.
The following future exposure pathways were found to present a potential risk exceeding EPA's
cancer risk range and non-cancer hazard index at the Site:
• Future exposure of a resident (adult and young child) to upland soils (by ingestion and
dermal contact) at the former residence, garage, and storage area;1
• Future exposure of a resident (adult and young child) to indoor air (by inhalation) at the
former drum disposal area;2
• Future exposure of a resident (adult and young child) to untreated groundwater (by
ingestion, dermal contact, and inhalation) from Groups 1 and 2 and Groups 3-6
monitoring wells;3 and
• Future exposure of a facility worker to untreated groundwater (by ingestion and dermal
contact) from Groups 3-6 monitoring wells."
! For future residential upland soil exposures, exposure durations of 24 years and 6 years, respectively, were presumed for an
adult and young child. Body weights of 70 kg and 15 kg were used for the adult and child, respectively. Dermal contact was
assumed with 5,700 cm' of surface area for the adult and 2,800 cm1 for the child. Future upland soil exposures were assumed to
occur 150 days/year.
2 For future residential indoor air exposures, exposure durations of 24 years and 6 years, respectively, were presumed for an adult
and young child. Future indoor air exposures were assumed to occur 24 hours/day for 350 days/year,
1 For future residential exposures to untreated groundwater, drinking water ingestion rates of 1.98 L/day and 1.3 L/day for the
adult and young child, respectively, were assumed. An exposure frequency of 350 days/year was used for a combined exposure
duration of 30 years. Dermal contact was assumed with 18,000 cm2 of surface area for the adult, and 6,600 cm2 for the child.
Showers/baths were assumed to occur 350 days/year for 0.58 hr/day for the adult and I hr/day for the child. Airborne
concentrations of volatile compounds released during showering/bathing were estimated using the Foster and Chrostowski
shower model,
4 For future facility worker exposures to untreated groundwater, a drinking water ingestion rate of 1.15 L/day was assumed. An
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Section 3: Toxicity Assessment
In the Human Health Risk Assessment, EPA assessed the potential for cancer risks and non-
cancer health effects of COCs at the Site.
The potential for carcinogenic effects is evaluated with chemical-specific cancer slope factors
(CSFs) and inhalation unit risk values, A weight of evidence classification is available for each
chemical. CSFs have been developed by EPA from epidemiological or animal studies to reflect
a conservative "upper bound" of the risk posed by potentially carcinogenic compounds. That is,
the true risk calculated using the CSF is unlikely to be greater than the risk predicted. A
summary of the cancer toxicity data relevant to the chemicals of concern is presented in Table G-
5.
The potential for non-cancer health effects is quantified by reference dose (RfD) for oral
exposure and reference concentrations (RfCs) for inhalation exposures. RfDs and RfCs have
been developed by EPA and they represent an estimate (with uncertainty spanning perhaps an
order of magnitude) of a daily exposure that is likely to be without an appreciable risk of
deleterious health effects during a lifetime. RfDs and RfCs are derived from epidemiological or
animal studies and incorporate uncertainty factors to help ensure that adverse health effects will
not occur. A summary of the non-carcinogenic toxicity data relevant to the chemicals of concern
at the Site is presented in Table G-6.
Section 4: Risk Characterization
Risk characterization combines estimates of exposure with toxicity data to estimate potential
health effects that might occur if no actions were taken.
Excess lifetime cancer risks were determined for each exposure pathway by multiplying the daily
intake levels (see Section 2: Exposure Assessment) by the Cancer Slope Factor (CSF) or by
comparison to the unit risk value. These toxicity values are conservative upper bound estimates,
approximating a 95% upper confidence limit, of the increased cancer risk from a lifetime
exposure to a chemical. Therefore, the true risks are unlikely to be greater than the risks
predicted. Cancer risk estimates are expressed as a probability, e.g., one in a million. Scientific
notation is used to express probability. One in a million risk (1 in 1,000,000) is indicated by 1 x
10~6 or 1E-06. In this example, an individual is not likely to have greater than a one in a million
chance of developing cancer over a lifetime as a result of exposure to the concentrations of
chemicals at a site. All risks estimated represent an "excess lifetime cancer risk" in additional to
the background cancer risk experienced by all individuals over a lifetime. The chance of an
exposure frequency of 250 days/year was used with an exposure duration of 25 years. Dermal contact was assumed with 2,077
cm2 of surface area. Dermal contact with groundwater was assumed to occur 250 days/year for 0,01 hr/cvcnt with 16 events/day
presumed.
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individual developing cancer from all other (non-site related) causes has been estimated to be as
high as one in three. EPA's generally acceptable risk range for site related exposure is 10"4to
10"6. Current EPA practice considers carcinogenic risks to be additive when assessing exposure
to a mixture of hazardous substances.
In assessing the potential for adverse effects other than cancer, a hazard quotient (HQ) is
calculated by dividing the daily intake by the RfD or RfC. A HQ < 1 indicates that an exposed
individual's dose of a single contaminant is less than the RfD or RfC and that a toxic effect is
unlikely. The Hazard Index (HI) is generated by adding the HQs for all chemical(s) of concern
that affect the same target organ (e.g., liver) within or across those media to which the same
individual may reasonably be exposed. A HI < 1 indicates that toxic non-carcinogenic effects
are unlikely.
The following is a summary of the media and exposure pathways that were found to present a
risk exceeding EPA's cancer risk range and non-cancer hazard index at the Site. Only those
exposure pathways deemed relevant to Site conditions are presented in this ROD. Readers are
referred to Section 3.4 and Tables 3-32 through 3-39 of the baseline human health risk
assessment for a more comprehensive risk summary of all exposure pathways evaluated for all
chemicals of potential concern and for estimates of the central tendency risk.
Resident at the Former Garage and Storage Area
Table G-7 depicts the carcinogenic risk summary for the chemicals of concern in upland soils
evaluated to reflect potential future residential exposure corresponding to the RME scenario. For
the future young child and adult resident, carcinogenic risk exceeded the EPA acceptable risk
range oflO"4 to 10~6. The exceedanee was due primarily to the presence of carcinogenic
polycyclic aromatic hydrocarbons (benzo(a)anthracene, benzo(a)pyrene, bcnzo(b)fluoranthene.
benzo(k)fluoranthene, dibenz(a,h)anthracene, and indeno(l ,2,3-cd)pyrene) in upland soils.
Resident at the Former Drum Disposal Area
Table G-8 depicts the non-carcinogenic risk summary for the chemicals of concern in indoor air
evaluated to reflect potential future residential exposure corresponding to the RME scenario. For
the future young child and adult resident, non-carcinogenic risk exceeded the EPA acceptable
target organ HI of 1. The exceedanee was due primarily to the presence of toluene and xylenes
in groundwater with the potential to impact indoor air via the subsurface vapor intrusion
pathway. The contribution of soil VOCs to the indoor air pathway was not quantitatively
evaluated in the risk assessment. However, based on the residual levels of VOCs in soils at the
FDDA, their presence may contribute to potential future indoor air impacts.
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Residential Groundwater Use
Tables G-9 through G-12 depict the carcinogenic and non-carcinogenic risk summary for the
chemicals of concern in future residential wells evaluated to reflect potential future potable water
exposure corresponding to the RME scenario, under the assumption that on-site groundwater
from beneath the Landfill Lobes (Groups 1 and 2) and beyond the Landfill Lobes (Groups 3-6)
migrates to potable wells installed on the Site, adjacent to or downgradient of the Site in the
future. For the future resident using untreated groundwater as household water, carcinogenic and
non-carcinogenic risks exceeded the EPA acceptable risk range of 10"4 to 10"6 and/or a target
organ HI of 1 for groundwater. The exceedances were due primarily to the presence of 1,4-
dioxane, 4-methyl-2-pentanone, benzene, methylene chloride, naphthalene, tetrachlorocthene,
tetrahydrofuran, toluene, triehloroethene, vinyl chloride, methylphenols, N-nitrosodi-n-
butylamine, N-nitrosopyrrolidine, arsenic, cadmium, and manganese in Group 1 and 2
groundwater, and 1,4-dioxane, 1,2-dichloroethane, 4-methyl-2-pentanone, acrylonitrile, benzene,
carbon tetrachloride, ethyl methacrylate, ethylbenzene, methylene chloride, tetrahydrofuran,
toluene, vinyl chloride, xylenes, bis(2-ethylhexyl)phthalate, antimony, arsenic, beryllium,
manganese, and zinc in Groups 3-6 groundwater.
Facility Worker Groundwater Use
Tables G-13 and G-14 depict the carcinogenic and non-carcinogenic risk summary for the
chemicals of concern in future commercial wells evaluated to reflect potential future potable
water exposure corresponding to the RME scenario, under the assumption that on-site
groundwater from beyond the landfill lobes (Groups 3-6) migrates to potable wells installed on
the Site, adjacent to or downgradient of the Site in the future. For the future facility worker
using untreated groundwater as potable water, carcinogenic and non-carcinogenic risks exceeded
the EPA acceptable risk range of 10"4 to 10"6 and/or a target organ HI of 1 for groundwater. The
exceedances were due primarily to the presence of 1,4-dioxane, 4-methyl-2-pentanone,
acrylonitrile, vinyl chloride, and arsenic in Groups 3-6 groundwater.
Facility Worker at the Former Drum Disposal Area
Table G-15 depicts the non-carcinogenic risk summary for the chemicals of concern in indoor air
evaluated to reflect potential future commercial exposure corresponding to the RME scenario.
For the future facility worker, non-carcinogenic risk exceeded the EPA acceptable target organ
HI of 1. The exceedance was due primarily to the presence of xylenes in groundwater with the
potential to impact indoor air via the subsurface vapor intrusion pathway. The contribution of
soil VOCs to the indoor air pathway was not quantitatively evaluated in the risk assessment.
However, based on the residual levels of VOCs in soils at the FDD A, their presence may
contribute to potential future indoor air impacts.
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Section 5: Uncertainties
Trichloroethene is currently being re-evaluated for carcinogenic potency by EPA. The high-end
of the range of oral slope factors and unit risk values was used for risk estimation. This approach
may have resulted in an overestimate of the risk associated with trichloroethene in groundwater.
In addition, toxicity values of surrogate compounds were used for compounds with similar
structures lacking toxicity values, resulting in either an underestimate or overestimate of risk.
These uncertainties will be periodically reviewed to address changes in and the availability of
toxicity values for these compounds.
For the groundwater dermal contact pathway, risk associated with dermal absorption of
chlorinated organic compounds may be underestimated. Permeability constants for the
chlorinated organic compounds such as 1,2-dichloroethane, tetrachlorocthcne, trichloroethene,
and vinyl chloride tend to be underestimated by the correlation modeling. This uncertainty may
result in an underestimation of risk. In addition, because there is greater uncertainty associated
with the correlation modeling for some compounds, risk associated with dermal absorption could
not be quantified for some contaminants, including Aroclor-1254. This uncertainty may also
result in an underestimation of risk. These uncertainties will be periodically reviewed to address
changes in the dermal absorption values for these compounds.
Airborne concentrations of volatile compounds for the showering/bathing scenario and for
indoor/outdoor air were estimated using accepted EPA exposure models. The use of modeling to
estimate airborne concentrations of volatile compounds likely results in an over-estimate of risk
since conservative assumptions were employed in the exposure modeling. In addition, the
contribution of soil volatile compounds to the vapor intrusion pathway was not quantified.
Though this may potentially underestimate the impact of volatile compounds from the subsurface
on indoor air, the extent of the bias is likely to be low due to the lower prevalence and
concentration of volatile compounds in soils relative to groundwater.
2. Ecological Risk Assessment
A baseline ecological risk assessment (BERA) was completed for the Sutton Brook Disposal
Area Site to evaluate the likelihood and magnitude of potential ecological effects associated with
historical disposal practices. The BERA evaluated the potential for contaminants to impact
ecological receptor populations exposed to: upland soils at and outside the former drum disposal
area (FDDA); surface water, sediments, and wetland soils in Sutton Brook and its associated
wetlands; and sediments and surface water in the man-made pond located south of the Southern
landfill lobe.
Section 1: Identification of Chemicals of Concern
Chemicals of Potential Concern (COPCs) were identified in the Screening Level Ecological Risk
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Assessment (SLERA) using effects-based screening involving the comparison of maximum
contaminant concentrations to ecological benchmarks for each medium and exposure area, and
included all COPCs that would bioaccumulate. The refinement of COPCs in the BERA
identified COPCs based on exeeedance of no observed-adverse effects level (NOAEL) screening
values, resulting in an NOAEL HQs greater than 1.0. Data used to identify COPCs are
summarized in Table G-16 (Upper Sutton Brook surface water), Table G-17 (Upper Sutton Brook
sediments), Table G-18 (Aquatic Wetland surface water), Table G-19 (Aquatic Wetland
sediments), Table G-20 (Wetland Soil), Table G-21 (Site Pond surface water), Table G-22 (Site
Pond sediments), and Table G-23 (Upland Soil),
The COPCs identified in Upper Sutton Brook surface water include one pesticide (4,4'-DDT),
three volatile organic chemicals (ethylbenzene, xylenes, and toluene), and three dissolved metals
(barium, manganese and iron). COPCs identified in Upper Sutton Brook sediments include ten
VOCs (1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, 4-methyl-2-pentanone, acetone, carbon
disulfide, ehloroethane, ethylbenzene, naphthalene, toluene, and xylenes), three semi-volatile
organic chemicals (2-methylphenol, 3-/4-methyIphenol, and benzo(a)pyrene), and three metals
(arsenic, iron, and manganese).
The COPCs in the Aquatic Wetland surface water include VOCs (ethylbenzene, toluene, and
xylenes) and nine metals (aluminum, arsenic, barium, copper, iron, lead, manganese, nickel and
zinc). COPCs identified in the Aquatic Wetland sediments include three VOCs (acetone,
ehloroethane, and toluene), one SVOC (benzoic acid), and five metals (arsenic, beryllium, iron,
mercury, and selenium).
The COPCs in the Wetland soils include one pesticide (aldrin), six SVOCs
(benzo(b)fluoranthene, benzoic acid, chrysene, fluoranthene, phenanthrene, and pyrene), and five
metals (arsenic, manganese, mercury, selenium, and vanadium).
The COPCs identified in the Site Pond surface water include three dissolved metals (barium,
manganese, and zinc). COPCs identified in the Site Pond sediments include two VOCs (acetone
and carbon disulfide), and arsenic.
The Upland soils evaluated in the SLERA, included both the former drum disposal area (FDD A),
as well as other upland areas of the Site, COPCs identified within the Upland soils include one
pesticide (4-4'-DDT), five VOCs (1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, ethylbenzene,
xylenes, and toluene), eight SVOCs (1,2,4-trichlorobenzene, 2,4-dimethylphenol, 4,6-dinitro-o-
cresol, bis(2-ethyihexyl)phthalate, di-n-butylphthalate, di-n-octylphthalate, fluoranthene, and
naphthalene) and six metals (chromium, copper, lead, mercury, vanadium, and zinc). Among
these, the maximum values of eight COPCs were measured in sample SB-3(G4) within the
FDDA.
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Section 2: Exposure Assessment
For purpose of the exposure assessment, the Site was divided into five habitat areas, including
Upper Sutton Brook, Aquatic Wetland, Site Pond, Wetland Soil, and Upland Soil (including
FDDA). Based on the conceptual site model, complete exposure pathways were identified,
sampled, tested, and evaluated in each habitat area separately. Consistent with the site
conceptual model, exposure pathways, assessment endpoints, and measurement endpoints are
summarized in Table G-24.
The majority of the Site is unpaved and relatively flat, aside for the steeply sloped landfill lobes.
Outside the landfill lobes, the Site primarily consists of wetlands, including several individual
wetland areas (red maple swamp/floodplain associated with Sutton Brook [greater than 50 acres],
small man-made pond [approximately 2 acres], man-made areas subject to flooding [small
forested wetland area and a borrow pit], and an emergent wetland area).
The main hydrologic feature at the Site is Sutton Brook and associated tributaries and wetlands.
Sutton Brook is a medium gradient stream that includes both moderately moving water through
established banks and slower moving water through much wider and less-established channels.
Sutton Brook flows east to west through the property and divides the landfill into the Northern
and Southern Lobes. Sutton Brook originates in an upland area to the north of the Site and flows
off site with discharge to the Shawsheen River approximately 2,500 feet northwest of South
Street.
The ground surface across the Site consists of the landfill lobes, fill areas, wetland soils, and an
upper sand layer. The upland habitat area of the Site, outside of the landfill lobes, includes the
generally disturbed and impacted areas around the former residence/garage, the former drum
disposal area and associated work areas near the former entrance to the landfill.
The Site is bounded by a piggery, greenhouses, stables, and a wooded area to the north; a
wooded area, composting operation, cattle feedlot, Route 93, and the Boston & Maine railroad
line to the east; wetlands, conservation land and open space owned by the Town of Tewksbury,
and a number of residences along Carleton Road to the south; and wetlands and a number or
residences to the west.
Based on consultation with U.S. Fish and Wildlife Service, there are no federally-listed
proposed, threatened or endangered species or critical habitat under the jurisdiction of the
USFWS known to occur in the project area. Consultation with Massachusetts Natural Heritage
and Endangered Species Program (MNHESP), indicated the potential occurrence of an
endangered moth, the New Jersey Tea Inchworm. A butterfly species of Special Concern, the
frosted elfin, had been documented as to occur in the vicinity of the Site. However, based on
habitat characterization conducted as part of the risk assessment, the MNHESP species of
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concern are not considered likely to occur at the Site due to the lack of available habitat,
including critical host plant species.
Potential receptors in Upper Sutton Brook include aquatic invertebrate and fish populations
exposed to COPCs in surface water or sediments. Aquatic invertebrate, amphibian populations,
and avian species were the receptors used in the Site Pond and Aquatic Wetland habitat areas.
The Wetland Soil habitat area was evaluated using terrestrial plants, soil invertebrates, and small
terrestrial mammal (short-tail shrew and eastern cottontail rabbit) receptors. Soils in the FDDA
were evaluated for terrestrial plants, soil invertebrates, and carnivorous bird (American robin)
receptors. Upland soils (excluding the FDDA) were evaluated for receptors including terrestrial
plants and soil invertebrates, and terrestrial wildlife (meadow vole and American robin).
Section 3: Ecological Effects Assessment
The risk to receptors in aquatic type habitat areas (Aquatic Wetland, Upper Sutton Brook, and
Site Pond) was evaluated on a screening level by comparing measured concentrations to effects-
based NOAEL surface water quality benchmarks, sediment quality benchmarks, and/or on the
basis of bioavailability as determined by acid volatile sulfide/simultaneous extracted metals
(AVS/SEM) analysis of sediments. The screening-level risk to receptors in terrestrial type
habitat areas (Wetland, Upland, and FDDA) was evaluated by comparison of measured soil
concentrations to effects-based NOAEL soil benchmarks for terrestrial plants and soil
invertebrates, and wildlife toxicity reference values (TRVs) that were derived site-specifically
and used in food chain exposure risk models.
The site channel portion of the Brook directly between the landfill lobes was evaluated by
comparison of five surface water and sediment samples to effects-based NOAEL benchmarks in
the screening-level step. Further assessment of ecological effects of exposure in the site channel
portion of the Brook (located between the landfill lobes) was not conducted in the BERA,
because of the assumption that a remedy would have to address the high risk of COPCs in the
site channel.
Potential baseline risk of the COPCs on receptors in all reaches of the Upper Sutton Brook, with
the exception of surface water and sediments in the site channel, were evaluated by effects-
based, LOAEL benchmarks. Whole sediment toxicity testing was performed to evaluate the
potential toxicity of selected Southern Tributary sediment arsenic concentrations on benthic
invertebrate populations. Toxicity testing consisted of 10-day whole sediment toxicity tests
using the amphipod Hyalella azteca and dipteran aquatic insect Chironomus tentarn,
Baseline risk to receptors in the Aquatic Wetland and Site Pond habitat areas was evaluated for
aquatic invertebrates and amphibians using effects-based LOAEL benchmarks for surface water
and sediments and semi-aquatic wildlife using TRVs derived site-specifically in food chain
models (Table G-23).
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Baseline risk to receptors in the Wetland soil habitat area was evaluated using effects-based,
LOAEL benchmarks for terrestrial plants, soil invertebrates, and semi-aquatic wildlife using
TRVs derived site-specifically in food chain models (Table G-23).
Baseline risk to receptors in the Upland Soil (excluding FDDA) habitat area was evaluated using
effects-based LOAEL benchmarks for terrestrial plants, soil invertebrates, and terrestrial wildlife
using TRVs derived site-specifically in food chain models (Table G-23).
Section 4: Risk Characterization
Risks to aquatic, semi-aquatic and terrestrial receptors were determined to be significant in the
following habitat areas (Table G-25):
• Upper Sutton Brook - site channel (sediments directly between the landfill lobes);
Unacceptable risk to aquatic invertebrates based on exposure to 1,3,5-trimethylbenzene,
ethyl benzene, and xylenes, among other contaminants (Table G-25). These risks are
based on exceedance of effects-based NOAEL benchmarks in the screening-level
ecological risk assessment.
• Upper Sutton Brook - site channel (surface water directly between the landfill lobes):
Unacceptable risk to aquatic life (e.g., fish, amphibians, invertebrates) from exposure to
4,4'-DDT, ethylbenzene, toluene, and xylenes. These risks are based on exceedance of
effects-based NOAEL surface water benchmarks or relevant water quality standards.
• Upland Soil (FDDA): Unacceptable risk to terrestrial plants from bis(2-
ethylhexyl)phthalate, ethylbenzene, naphthalene, and xylenes; unacceptable risks to soil
invertebrates from 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, ethylbenzene,
toluene, and xylenes. Unacceptable risk to terrestrial wildlife (American robin) based on
food chain model dietary exposure to 1,2,4-trimethylbenzene, bis(2-ethylhexyl)phthalate,
di-n-octylphthalate, and xylenes.
• Upland Soil (excluding FDDA): Unacceptable risk to terrestrial wildlife (American
robin) based on food chain dietary exposure to di-n-octylphthalate and lead.
Unacceptable risk to soil invertebrates from exposure to zinc.
Section 5: Uncertainties
Ecological risk assessments are subject to a variety of uncertainties as the result of both the
assumptions used to describe the site conditions, habitats and estimated receptor exposures, plus
variability in receptor exposure and toxicological response. As a result, the assessment must
estimate or infer the information concerning individuals to reach a conclusion about risk at the
population level.
The BERA provided a detailed evaluation of potential sources of uncertainty in the calculation of
risk (BERA Table 4-57). These uncertainties include a lack of medium-specific and species-
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specific benchmarks and toxicity data for some of the COPCs. Extrapolation of toxicity data
among species and limited data on the bioavailability of COPCs in each medium are factors that
contribute to uncertainty in the use of benchmarks.
Additional uncertainties are associated with dietary modeling because concentrations of the
COPCs in wildlife prey tissue was not measured but modeled instead using conservative uptake
factors.
The risks identified in the site channel portion of the Upper Sutton Brook and Upland Soil
habitat area of the FDDA, were not further evaluated in the BERA due to the presumption of a
remedy to address the high risk screening-level. Consequently, the risk characterization for these
habitat areas is based on effects-based, NOAEL screening values without additional site-specific
effects analysis,
3, Basis for Response Action
The baseline human health and ecological risk assessments revealed that:
• a future resident potentially exposed to compounds of concern in soils via ingestion
and dermal contact may present an unacceptable human health risk (exceedance of
10"4 cancer risk);
• a future resident or facility worker potentially exposed to compounds of concern in
groundwater via inhalation may present an unacceptable human health risk (HI of
concern);
• a future resident or facility worker potentially exposed to compounds of concern in
groundwater via ingestion may present an unacceptable human health risk(exeeedanee
of 10~4 cancer risk and HI of concern); and
• unacceptable ecological risk exists to terrestrial plans and wildlife in Upland Soil,
aquatic invertebrates in Upper Sutton Brook sediments and aquatic life in Upper
Sutton Brook surface water.
Actual or threatened releases of hazardous substances from this Site, if not addressed by
implementing the response action selected in this ROD, may present an imminent and substantial
endangerment to public health, welfare, or the environment. Groundwater, soils, surface water,
and sediments are to be the focus of the remedial action.
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H. REMEDIATION OBJECTIVES
Based on preliminary information relating to types of contaminants, environmental media of
concern, and potential exposure pathways, response action objectives (RAOs) were developed to
aid in the development and screening of alternatives. These RAOs were developed to mitigate,
restore and/or prevent existing and future potential threats to human health and the environment.
The RAOs for the remedy for the Sutton Brook Disposal Area are to:
• Prevent direct contact/ingestion of landfill contents for the protection of human and
ecological receptors;
• Prevent direct contact and ingestion of residual levels of SVOCs and VOCs in soils in
the FDDA and metals and SVOCs in soils in the GSA above applicable human health
or ecological based criteria;
• Prevent direct exposure to impacted surface water and sediments in those areas of the
wetlands and brook determined by the ecological risk assessment;
• Prevent contaminant migration via surface run-off and erosion through the "source
areas" to surface water or sediments in the brook or wetlands for the protection of
ecological receptors;
• Control landfill gas;
• For the protection of potential human receptors, reduce contaminant leaching via
infiltration through the "source areas" with subsequent migration to groundwater at
concentrations in excess of State or Federal Maximum Contaminant Levels (MMCLs
or MCLs) and applicable groundwater quality standards. For contaminants where no
State or Federal drinking water standard has been established, reduce leaching such
that groundwater concentrations will not exceed human health risk-based levels (i.e.,
greater than the carcinogenic target risk range of 10"4 to 10'6 or non-carcinogenic
target organ Hazard Index of 1);
• For the protection of potential human receptors, prevent exposure to groundwater
impacted by site contaminants at concentrations that exceed State or Federal drinking
water standards (MMCLs or MCLs). For contaminants where no State or Federal
drinking water standard has been established, prevent exposure to concentrations
which exceed human health risk-based levels (i.e., greater than the carcinogenic target
risk range of 10"4 to 10*6 or non-carcinogenic target organ Hazard Index of 1). For
contaminants that are a concern with respect to vapor intrusion, prevent exposure to
indoor air concentrations that are not protective of human health;
• Limit the discharge of impacted groundwater to Sutton Brook to prevent site
contaminants in surface water or sediments from exceeding ecological based criteria
or unacceptable levels of risk to ecological receptors;
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• Prevent migration of contaminants off-site via groundwater or surface water at levels
in excess of Federal and/or State standards/criteria or unacceptable levels of risk to
human or ecological receptors.
More specifically, the remedy will seek;
- To reduce the potential exposure of a future resident to carcinogenic polycyclic aromatic
hydrocarbons (benzo(a)anthracene, benzo(a)pyrene, benzo(b)fl uoranthene,
benzo(k)fluoranthene, dibenz(a,h)anthracenc, and indeno( 1,2,3-cd)pyrene) in upland soils via
direct contact that may present a human health risk in excess of 10" cancer risk such that the
cancer risk attributable to this medium is within the range of 10'4to 10"6 and complies with
ARARs
- To reduce the potential exposure of a future resident to toluene and xylenes in groundwater via
inhalation that may present a human health risk in excess of III>1 such that the non-cancer risk
attributable to this medium is a HI which does not exceed one and complies with ARARs
- To reduce the potential exposure of a future resident to acrylonitrile, benzene, carbon
tetrachloride, ethyl mcthacrylatc, ethylbenzene, methylene chloride, xylenes, 1,2-
dichloroethane, 1,4-dioxanc, 4-methyl-2-pentanone, bis(2-ethylhexyl)phthalate, naphthalene,
tetrachloroethene, tetrahydrofuran, toluene, triehloroethene, vinyl chloride, methylphenols, N-
nitrosodi-n-butylamine, N-nitrosopyrrolidine, antimony, arsenic, beryllium, cadmium, and
manganese and zinc in groundwater via ingestion that may present a human health risk in excess
of 10"4 cancer risk, or a HI>1 such that the cancer and non-cancer risk attributable to this medium
are within the range of 10"4 to 1Q"6 and a HI which does not exceed one and complies with
ARARs
- To reduce the potential exposure of a future facility worker to 1,4-dioxane, 4-methyl-2-
pentanone, acrylonitrile, vinyl chloride, and arsenic in poundwater via ingestion that may
present a human health risk in excess of 10"4 cancer risk or HIM such that the cancer and non-
cancer risk attributable to this medium is within the range of 10*4 to 10"6 and a HI which does not
exceed one and complies with ARARs
- To reduce the potential exposure of a future facility worker to xylenes in groundwater via
inhalation that may present a human health risk in excess of HI>1 such that the non-cancer risk
attributable to this medium is a HI which does not exceed one and complies with ARARs
- To reduce the potential exposure of aquatic invertebrates to 1,3,5-trimethylbenzene,
ethylbenzene, and xylenes, among others in sediments directly between the landfill lobes that
may present an ecological risk in excess of NOAEL benchmarks such that the ecological risk
attributable to this medium complies with ARARs
- To reduce the potential exposure of aquatic life (e.g., fish, amphibians, invertebrates) to 4,4*-
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DDT, ethylbenzene, toluene, and xylenes in surface water directly between the landfill lobes that
may present an ecological risk in excess of effects-based, NOAEL surface water benchmarks or
water quality standards such that the ecological risk attributable to this medium complies with
ARARs
- To reduce the potential exposure of terrestrial plants to bis(2-ethylhexyl)phthalate,
ethylbenzene, naphthalene, and xylenes; soil invertebrates from 1,2,4-trimethylbenzene, 1,3,5-
trimethylbenzene, ethylbenzene, toluene, and xylenes; and terrestrial wildlife (American robin)
based on food chain model dietary exposure to 1,2,4-trimethylbenzene, bis(2-
ethylhexyl)phthalate, di-n-octylphthalate, and xylenes in soils at the FDDA such that the
ecological risk attributable to this medium complies with ARARs
- To reduce the potential exposure of American robin based on food chain dietary exposure to
di-n-octylphthalate and lead; and soil invertebrates from exposure to zinc in upland soils
(excluding FDDA) such that the ecological risk attributable to this medium complies with
ARARs
I. DEVELOPMENT AND SCREENING OF ALTERNATIVES
1. Statutory Requirements/Response Objectives
Under its legal authorities, EPA's primary responsibility at Superfund sites is to undertake
remedial actions that are protective of human health and the environment. In addition, Section
121 of CERCLA establishes several other statutory requirements and preferences, including: a
requirement that EPA's remedial action, when complete, must comply with all Federal and more
stringent State environmental and facility siting standards, requirements, criteria or limitations,
unless a waiver is invoked; a requirement that EPA select a remedial action that is cost-effective
and that utilizes permanent solutions and alternative treatment technologies or resource recovery
technologies to the maximum extent practicable; and a preference for remedies in which
treatment which permanently and significantly reduces the volume, toxicity or mobility of the
hazardous substances is a principal element over remedies not involving such treatment.
Response alternatives were developed to be consistent with these Congressional mandates.
2. Technology and Alternative Development and Screening
CERCLA and the National Contingency Plan (NCP) set forth the process by which remedial
actions are evaluated and selected. In accordance with these requirements, a range of
alternatives were developed for the Site.
As described earlier (Sections E. and G.), the Sutton Brook Disposal Area Site is comprised of
two major source areas (the Landfill Lobes and the Former Drum Disposal Area), one minor
source area (the Garage and Storage Area), and the Downgradient Groundwater Area. The
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RI/FS (including the Risk Assessment) studied and evaluated these areas discretely regarding the
nature and extent of contamination, as well as with regard to evaluating potential risk. Logically,
this led to evaluating and screening technologies, as well as developing, screening and evaluating
remedial alternatives, discretely, for each area.
With respect to source control, the RI/FS developed a range of alternatives (for the Former Dram
Disposal Area and the Garage and Storage Area) in which treatment that reduces the toxicity,
mobility, or volume of the hazardous substances is a principal element. This included an
alternative that removes or destroys hazardous substances to the maximum extent feasible,
eliminating or minimizing to the degree possible the need for long term management. This range
also included: alternatives that treat the principal threats posed by the Site, but vary in the degree
of treatment employed and the quantities and characteristics of the treatment residuals and
untreated waste that must be managed; alternative(s) that involve little or no treatment but
provide protection through engineering or institutional controls; and a no action alternative.
Consistent with EPA's Guidance on Presumptive Remedy for CERCLA Municipal Landfill
Sites, alternatives in which treatment is a principal element were not developed for the Landfill
Lobes area because it was assumed that the Landfill Lobes would be capped.
With respect to ground water, the RI/FS developed a limited number of remedial alternatives (for
the Landfill Lobes, the Former Drum Disposal Area and the Downgradient Groundwater Area)
that attain site specific remediation levels within different time frames using different
technologies, and a no action alternative. The Garage and Storage Area is not considered a
source of groundwater contamination.
As discussed in Section 4 of the FS, soil and groundwater treatment technology options were
identified, assessed and screened based on implementability, effectiveness, and cost for each
discrete area. These technologies were combined into alternatives and screened in Section 5.
Section 6 of the FS presented the remedial alternatives developed by combining the technologies
identified in the previous screening process. The purpose of the initial screening was to narrow
the number of potential remedial actions for further detailed analysis, while preserving a range of
options. Each alternative was then evaluated in detail in Section 8 of the FS.
In summary, of the 2 source control and 7 management of migration alternatives for the Landfill
Lobes screened in Section 5 of the FS, 2 source control and 4 management of migration
alternatives were retained as possible options for the cleanup of this area of the Site. From this
initial screening, remedial options were combined, and 5 Landfill Lobe alternatives were selected
for detailed analysis. For the Former Drum Disposal Area, of the 5 source control and 7
management of migration remedial alternatives screened in Section 5 of the FS, 3 source control
and 4 management of migration alternatives were retained as possible options for cleanup of this
area of the Site. From this initial screening, remedial options were combined, and 5 Former
Drum Disposal Area alternatives were selected for detailed analysis. For the Garage and Storage
Area, of the 4 source control remedial alternatives screened , 2 alternatives were retained as
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possible options and underwent detailed analysis. For the Downgradient Groundwater Area, of
the 5 management of migration alternatives screened, 4 alternatives were retained as possible
options for the cleanup of this area and underwent detailed analysis.
J. DESCRIPTION OF ALTERNATIVES
This Section provides a narrative summary of the alternatives evaluated for each of these areas of
the Site:
Landfill Lobes
- Former Drum Disposal Area
Garage and Storage Area
Downgradient Groundwater
1. Landfill Lobe Alternatives Analyzed
Each of the 5 Landfill Lobe alternatives is summarized below. A more complete, detailed
presentation of each alternative is found in Section 8 of the FS (Detailed analysis of Landfill
Lobe alternatives is found in attached Tables LF-1 through LF-4).
The Landfill Lobe alternatives analyzed for the Site include:
Alternative LF-1 - No Action
Alternative LF-2a -
• Containment of Waste
Landfill Lobes will be capped with a low permeability RCRA Subtitle C waste cover
system.
• Restoration of Wetlands and Brook
Wetlands restoration will be required due to construction impacts (including excavation
of approximately 750 cubic yards of contaminated sediments).
• Partial Containment of Groundwater with a Vertical Barrier
Groundwater will be contained via a vertical barrier along a portion of the Southern Lobe
to limit the direction of groundwater migration and to eliminate future impacts to Sutton
Brook via groundwater discharge. The barrier is estimated to be 1,700 linear feet to a
depth of approximately 30 feet below current grade.
• Monitored Natural Attenuation (MNA) of Groundwater
Groundwater contamination will be addressed through natural attenuation processes. If
necessary, active groundwater remediation (extraction and treatment or an enhanced in-
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situ technology) would be implemented. Discussion of criteria to be used in determining
whether active groundwater remediation is necessary is located in Section L (The
Selected Remedy).
• Institutional Controls
This alternative will also include institutional controls to prohibit landfill excavation,
restrict the future use/access to the landfill, and restrict the future use of groundwater
until remedial goals are met.
• Monitoring, Operation and Maintenance
This alternative will monitor groundwater, surface water, landfill gas and leachate, and
conduct operation and maintenance activities for each component of the remedy (cap
repairs, mowing, groundwater treatment plant operation, etc.).
Alternative Lb"-2b -
• Containment of Waste
Landfill Lobes will be capped with a low permeability RCRA Subtitle C waste cover
system.
• Restoration of Wetlands and Brook
Wetlands restoration will be required due to construction impacts (including excavation
of approximately 750 cubic yards of contaminated sediments).
• Partial Containment of Groundwater with a Vertical Barrier
Groundwater will be contained via a vertical barrier along a portion of the Southern Lobe
to limit the direction of groundwater migration and to eliminate future impacts to Sutton
Brook via groundwater discharge. The barrier is estimated to be 1,700 linear feet to a
depth of approximately 30 feet below current grade.
• Active Groundwater Remediation
At the Southern Lobe, groundwater will be extracted and treated at the western edge of
the lobe (at the end of the containment barrier). Due to the wide range of contaminants in
groundwater, further pre-design studies will be required to develop the precise
combination of treatment processes. The treatment processes will likely include metals
precipitation, UV-oxidation, carbon adsorption and/or air stripping. Pre-design studies
may also demonstrate that an enhanced in-situ technology may be appropriate. Treated
groundwater will be discharged to the local publicly owned treatment works or to surface
water on-site. Because of lower contaminant concentrations, natural attenuation
processes would be utilized to address groundwater at the Northern Lobe.
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• Institutional Controls
This alternative will also include institutional controls to prohibit landfill excavation,
restrict the future use/access to the landfill, and restrict the future use of groundwater
until remedial goals are met.
• Monitoring; Operation and Maintenance
This alternative will monitor groundwater, surface water, landfill gas and leachate, and
conduct operation and maintenance activities for each component of the remedy (cap
repairs, mowing, groundwater treatment plant operation, etc.).
Alternative LF-3 -
• Containment of Waste
Landfill Lobes will be capped with a low permeability RCRA Subtitle C waste cover
system.
• Restoration of Wetlands and Brook
Wetlands restoration will be required due to construction impacts (including excavation
of approximately 750 cubic yards of contaminated sediments).
• Contaminated Groundwater Collection and Treatment
Groundwater extraction and treatment will be performed at the downgradicnt edges of
both the Southern and Northern Lobes. Treated groundwater will be discharged to the
local publicly owned treatment works or to surface water on-site.
• Institutional Controls
This alternative will also include institutional controls to prohibit landfill excavation,
restrict the future use/access to the landfill, and restrict the future use of groundwater
until remedial goals are met.
• Monitoring, Operation and Maintenance
This alternative will monitor groundwater, surface water, landfill gas and leachate, and
conduct operation and maintenance activities for each component of the remedy (cap
repairs, mowing, groundwater treatment plant operation, etc.).
Alternative LF-4 -
• Containment of Waste
Landfill Lobes will be capped with a low permeability RCRA Subtitle C waste cover
system.
• Re-routing of the Brook
Sutton Brook will be re-routed along the southern edge of the Southern Lobe,
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• Excavation of Impacted Sediment Hot Spots
Contaminated sediments from the original brook bed will be excavated (approximately
750 cubic yards).
• Partial Containment of Groundwater (Vertical Barrierj
Groundwater will be contained via a vertical barrier between the Southern Lobe and the
re-routed brook, The barrier is intended to prevent recontamination of the brook from
migration of contaminated groundwater.
• Groundwater Remediation
At the Southern Lobe, groundwater will be extracted and treated at the western edge of
the lobe (at the end of the containment barrier). Due to the wide range of contaminants in
groundwater, further pre-design studies will be required to develop the precise
combination of treatment processes. The treatment processes will likely include metals
precipitation, UV-oxidation, carbon adsorption and/or air stripping. Pre-design studies
may also demonstrate that an enhanced in-situ technology may be appropriate. Treated
groundwater will be discharged to the local publicly owned treatment works or to surface
water on-site. Because of lower contaminant concentrations, natural attenuation
processes would be utilized to address groundwater at the Northern Lobe.
• Institutional Controls
This alternative will also include institutional controls to prohibit landfill excavation,
restrict the future use/access to the landfill, and restrict the future use of groundwater
until remedial goals are met.
• Monitoring, Operation and Maintenance
This alternative will monitor groundwater, surface water, landfill gas and leachate, and
conduct operation and maintenance activities for each component of the remedy (cap
repairs, mowing, groundwater treatment plant operation, etc.).
2, Former Drum Disposal Area Alternatives Analyzed
Each of the 5 Former Drum Disposal Area alternatives is summarized below. A more complete,
detailed presentation of each alternative is found in Section 8 of the FS. (Detailed analysis of
Former Drum Disposal Area alternatives is found in attached Tables FDDA-1 through FDDA-
5).
The Former Dram Disposal Area alternatives analyzed for the Site include:
Alternative FDDA-1 - No Action
Alternative FDDA-2 -
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• Containment of Soils (with Cap)
Contaminated soils will be capped in place with a low permeability RCRA Subtitle C
waste cover system.
• Containment of Groundwater (through Extraction and Ex-Situ Treatment)
Groundwater will be extracted and treated to provide containment of the contaminated
plume utilizing an estimated 4 extraction wells to act as a hydraulic barrier. Treated
groundwater will be discharged to the local publicly owned treatment works or to surface
water on-site.
• Institutional Controls
This alternative will also include institutional controls to prohibit landfill excavation,
restrict the future use/access to the landfill and to restrict the future use of groundwater
until remedial goals are met.
• Monitoring, Operation and Maintenance
This alternative will monitor groundwater, and conduct operation and maintenance
activities (if necessary).
Alternative FDDA -3 ~
• Excavation, Treatment and/or Disposal of Soils
Approximately 8,900 cubic yards of soils contaminated in excess of site-specific cleanup
levels will be excavated for consolidation in the Landfill Lobes prior to lobe capping. If
it is determined to be more cost-effective, these soils may also be disposed of at an
appropriate off-site facility.
• Hydraulic Containment of Groundwater (through Extraction and Ex-Situ Treatment)
Groundwater will be extracted and treated to provide containment of the contaminated
plume utilizing an estimated 4 extraction wells to act as a hydraulic barrier. Treated
groundwater will be discharged to the local publicly owned treatment works or to surface
water on-site.
• Institutional Controls
This alternative will also include institutional controls to restrict the future use of
groundwater until remedial goals are met.
• Monitoring, Operation and Maintenance
This alternative will monitor groundwater, and conduct operation and maintenance
activities (if necessary).
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Alternative FDDA-4 -
• Excavation, Treatment and/or Disposal of Soils
Approximately 8,900 cubic yards of soils contaminated in excess of site-specific cleanup
levels will be excavated for consolidation in the landfill lobes prior to lobe capping. If it
is determined to be more cost-effective, these soils may also be disposed of at an
appropriate off-site facility.
• Groundwater Remediation (Focused Mass Reduction)
Groundwater contamination will be addressed through natural attenuation processes. If
necessary, active groundwater remediation (extraction and treatment or an enhanced in-
situ technology) would be implemented. Discussion of criteria to be used in determining
whether active groundwater remediation is necessary is located in Section L (The
Selected Remedy).
• Institutional Controls
This alternative will also include institutional controls to restrict the future use of
groundwater until remedial goals are met.
• Monitoring; Operation and Maintenance
This alternative will monitor groundwater, and conduct operation and maintenance
activities (if necessary).
Alternative FDDA-5 -
• Excavation, Treatment and/or Disposal of Soils
Approximately 8,900 cubic yards of soils, contaminated in excess of site-specific cleanup
levels, will be excavated for consolidation in the landfill lobes prior to lobe capping. If it
is determined to be more cost-effective, these soils may also be disposed of at an
appropriate off-site facility.
• Groundwater Extraction and Ex-Si tu Treatment for Area- Wide Contaminant Reduction
Groundwater extraction and treatment will be implemented over the impacted area
utilizing and estimated 5 extraction wells for an aggressive approach to meet groundwater
cleanup levels in this area in an accelerated timeframe. Treated groundwater will be
discharged to the local publicly owned treatment works or to surface water on-site.
• Institutional Controls
This alternative will also include institutional controls to restrict the future use of
groundwater until remedial goals are met.
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• Monitoring, Operation and Maintenance
This alternative will monitor groundwater, and conduct operation and maintenance
activities (if necessary).
3. Garage and Storage Area Alternatives Analyzed
Both of the Garage and Storage Area alternatives are summarized below. A more complete,
detailed presentation of each alternative is found in Section 8 of the FS.
Note: As described in Section G,, this area was evaluated in the risk assessment as the Former
Residence, Garage and Storage Area, The Former Residence portion of the property did not
present a potential risk under the exposure pathways evaluated in the risk assessment by EPA.
Because of this, alternatives were not developed for the Former Residence portion of the
property, and the Former Residence is not referred to in the alternatives or Selected Remedy
discussions.
(Detailed analysis of Garage and Storage Area alternatives is found in attached Tables GSA-1
and GSA-2).
The Garage and Storage Area alternatives analyzed for the Site include:
Alternative GSA-1 - No Action
Alternative GSA-2 -
• Soil Excavation and Disposal
Soils contaminated in excess of site-specific cleanup levels, will be excavated for
consolidation in the landfill lobes prior to lobe capping. If it is determined to be more
cost-effective, these soils may also be disposed of at an appropriate off-site facility.
4. Downgradient Groundwater Alternatives Analyzed
Each of the 4 Downgradient Groundwater alternatives is summarized below. A more complete,
detailed presentation of each alternative is found in Section 8 of the FS. (Detailed analysis of
Downgradient Groundwater alternatives is found in attached Tables DGGW-1 through
DGGW-4).
The Downgradient Groundwater alternatives analyzed for the Site include:
Alternative DGGW-1 - No Action
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Alternative DGGW-2 -
• In-Situ Remediation
Groundwater contamination will be addressed through natural attenuation processes with
a contingency for active groundwater treatment if necessary. Discussion of criteria to be
used in determining whether active groundwater remediation is necessary is located in
Section L (The Selected Remedy),
• Institutional Controls
This alternative will also include institutional controls to restrict the future use of
groundwater until remedial goals are met.
. Monitoring, Operation and Maintenance
This alternative will monitor groundwater, and conduct operation and maintenance
activities (if necessary).
Alternative DGGW-3 -
• Groundwater Containment and Treatment
Groundwater containment will be accomplished through extraction and treatment,
utilizing an estimated 3 extraction wells to minimize downgradient migration of
contaminated groundwater. Treated groundwater will be discharged to the local publicly
owned treatment works or to surface water on-site.
• Institutional Controls
This alternative will also include institutional controls to restrict the future use of
groundwater until remedial goals are met.
• Monitoring, Operation and Maintenance
This alternative will monitor groundwater, and conduct operation and maintenance
activities (if necessary).
Alternative DGGW-4 —
• Groundwater Extraction and Ex-Situ Treatment for Area-Wide Contaminant Reduction
This alternative is an aggressive approach, utilizing an estimated 10 extraction wells, that
seeks contaminant mass reduction through groundwater extraction and ex-situ treatment
of extensive volume of groundwater from throughout the downgradient groundwater
area. Treated groundwater will be discharged to the local publicly owned treatment
works or to surface water on-site.
• Institutional Controls
This alternative will also include institutional controls to restrict the future use of
groundwater until remedial goals are met.
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• Monitoring, Operation and Maintenance
This alternative will monitor groundwater, and conduct operation and maintenance
activities (if necessary),
K. SUMMARY OF THE COMPARATIVE ANALYSIS OF ALTERNATIVES
Section 121(b)(1) of CERCLA presents several factors that at a minimum EPA is required to
consider in its assessment of alternatives. Building upon these specific statutory mandates, the
NCP articulates nine evaluation criteria to be used in assessing the individual remedial
alternatives.
A detailed analysis was performed on the alternatives using the nine evaluation criteria in order
to select a site remedy. The following is a summary of the comparison of each alternative's
strength and weakness with respect to the nine evaluation criteria. These criteria are summarized
as follows:
Threshold Criteria
The two threshold criteria described below must be met in order for the alternatives to be eligible
for selection in accordance with the NCP:
1. Overall protection of human health and the environment addresses whether or not a
remedy provides adequate protection and describes how risks posed through each
pathway are eliminated, reduced or controlled through treatment, engineering controls, or
institutional controls.
2. Compliance with applicable or relevant and appropriate requirements (ARARs)
addresses whether or not a remedy will meet all Federal environmental and more
stringent State environmental and facility siting standards, requirements, criteria or
limitations, unless a waiver is invoked.
Primary Balancing Criteria
The following five criteria are utilized to compare and evaluate the elements of one alternative to
another that meet the threshold criteria:
3. Long-term effectiveness and permanence addresses the criteria that are utilized to
assess alternatives for the long-term effectiveness and permanence they afford, along
with the degree of certainty that they will prove successful.
4. Reduction of toxicity, mobility, or volume through treatment addresses the degree to
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which alternatives employ recycling or treatment that reduces toxicity, mobility, or
volume, including how treatment is used to address the principal threats posed by the
Site.
5. Short term effectiveness addresses the period of time needed to achieve protection and
any adverse impacts on human health and the environment that may be posed during the
construction and implementation period, until cleanup goals are achieved.
6. Implementability addresses the technical and administrative feasibility of a remedy,
including the availability of materials and services needed to implement a particular
option,
7. Cost includes estimated capital and Operation Maintenance (O&M) costs, as well as
present-worth costs.
Modifying Criteria
The modifying criteria are used as the final evaluation of remedial alternatives, generally after
EPA has received public comment on the RI/FS and Proposed Plan;
8. State acceptance addresses the State's position and key concerns related to the preferred
alternative and other alternatives, and the State's comments on ARARs or the proposed
use of waivers.
9. Community acceptance addresses the public's general response to the alternatives
described in the Proposed Plan and Rl/FS report.
Following the detailed analysis of each individual alternative, a comparative analysis, focusing
on the relative performance of each alternative against the nine criteria, was conducted. This
comparative analysis can be found in Section 8 of the FS, as well as in Tables 9-1,9-2,9-3 and
9-4 of the FS, and attached to this ROD as Tables K-l, K-2 K-3 and K-4.
The section below presents the nine criteria and a brief narrative summary of the alternatives
and the strengths and weaknesses according to the detailed and comparative analysis for each of
the areas evaluated in the FS. Only those alternatives which satisfied the first two threshold
criteria were balanced and modified using the remaining seven criteria.
1. Landfill Lobes
Overall Protection of Human Health and the Environment
Overall protection of human health and the environment addresses whether each alternative
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provides adequate protection of human health and the environment and describes how risks
posed through each exposure pathway are eliminated, reduced, or controlled, through treatment,
engineering controls, and/or institutional controls.
All of the alternatives evaluated, with the exception of LF-1 (the No Action Alternative), will be
protective of human health and the environment by eliminating, reducing, and controlling current
and future risks through treatment, containment and/or institutional controls.
Alternatives, LF-2as LF-2b, LF-3 and LF-4 address current and potential future exposure risks
through institutional controls, containment and treatment (LF-2a with a contingency for an active
groundwater treatment technology, if needed), restricting exposure to the landfill waste (through
containment and institutional controls), and preventing the use of groundwater in this area until
RAOs are attained.
Groundwater RAOs will be attained and exposure risks will be controlled with alternative LF-2
and LF-4 using containment (vertical barrier) and either in-situ natural attenuation processes
(LF-2a with a contingency for an active groundwater treatment technology, if needed) or focused
active treatment at the Southern Lobe and natural attenuation at the Northern Lobe (LF-2b); or
with alternative LF-3 through groundwater extraction and ex-situ treatment at both lobes.
Compliance with Applicable or Relevant and Appropriate Requirements
Section 121(d) of CERCLA requires that remedial actions at CERCLA sites at least attain legally
applicable or relevant and appropriate Federal and State requirements, standards, criteria, and
limitations which are collectively referred to as "ARARs, " unless such ARARs are waived under
CERCLA section 121(d)(4).
Applicable requirements are those substantive environmental protection requirements, criteria,
or limitations promulgated under Federal or State law that specifically address hazardous
substances, the remedial action to be implemented at the site, the location of the site, or other
circumstances present at the site. Relevant and appropriate requirements are those substantive
environmental protection requirements, criteria, or limitations promulgated
under Federal or State law which, while not applicable to the hazardous materials found at the
site, the remedial action itself, the site location or other circumstances at the site, nevertheless
address problems or situations sufficiently similar to those encountered at the site that their use
is well-suited to the site.
Compliance with ARARs addresses whether a remedy will meet all of the applicable or relevant
and appropriate requirements of other Federal and State environmental statutes or provides a
basis for invoking a waiver.
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Alternative LF-1 will not meet chemical specific ARARs as no remedial actions will be
performed to reduce concentrations in sediments, surface water and groundwater. Alternatives
LF-2a, LF-2b and LF-3 can be designed to comply with chemical, location and action specific
ARARs. Attainment of chemical specific ARARs with regard to groundwater will not occur
immediately, but rather, over a period of time once source control measures are implemented and
in-situ or ex-situ remedial processes break down contaminants. The estimated timeframe to
achieve the chemical specific ARARs for these alternatives (LF-2a, LF-2b and LF-4) are within
the same order of magnitude, estimated to be in the 65 to 200 year range. Alternative LF-3,
which incorporates groundwater extraction and ex-situ treatment, was estimated to meet cleanup
goals in a slightly quicker timeframe (50 to 165 years). Alternative LF-4 can be designed and
implemented to comply with applicable chemical and action specific ARARs; however the brook
re-routing component of this alternative will most likely not meet location specific ARARs.
Under inter alia Section 404 of the Clean Water Act and the Massachusetts Wetlands Protection
Act, it must be demonstrated that there is no practicable alternative to LF-4 that would be less
damaging, in terms of magnitude, to the resource areas. Because alternatives LF-2a, LF-2b and
LF-3 present viable options that are less damaging to the existing on-site resource areas, the
impacts to resource areas under LF-4 would not unavoidable.
As a result, alternatives LF-2a, LF-2b and LF-3 are the only alternatives that appear to be able to
be designed and implemented to comply with all ARARs.
Long-Term Effectiveness and Permanence
Long-term effectiveness and permanence refers to expected residual risk and the ability of a
remedy to maintain reliable protection of human health and the environment over time, once
clean-up levels have been met. This criterion includes the consideration of residual risk and the
adequacy and reliability of controls.
With the exception of the No-Action alternative, all alternatives provide a comparable level of
long term effectiveness and permanence in regards to the landfill waste. The effectiveness and
permanence are dependent on the adequacy of maintenance.
Alternatives LF-2a, LF-2b and LF-3 which incorporate sediment excavation provide the highest
level of long-term effectiveness for the brook sediments since the material is removed from the
area, preventing current and potential future exposure. Alternative LF-4 is effective in reducing
risks associated with the impacted sediments; however, since some of the contaminated
sediments remain in place (and covered), the long-term effectiveness is reduced compared to I.F-
2a, LF-2b and LF-3.
For groundwater, each alternative (with the exception of the No-Action alternative) prevents
future potential risks via institutional controls and/or groundwater remediation. Alternatives LF-
2a, LF-2b and LF-4 use a combination of a permanent vertical barrier for containment and a
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focused groundwater remedial action at the downgradient end of the barrier. Alternative LF-2a
incorporates a phased approach to the groundwater remedy, starting with monitored natural
attenuation (MNA) with a contingency for active groundwater treatment based on the monitoring
results. Alternatives LF-2b, LF-3 and LF-4 incorporate active treatment of groundwater (either
in-situ technologies or extraction and ex-situ treatment).
Overall, LF-2a, LF-2b and LF-4 provide a higher level of reliability in groundwater containment
over LF-3 since the vertical barrier is a permanent physical barrier; whereas, under alternative
LF-3, containment is dependent upon groundwater extraction. LF-2a. LF-2b, LF-3 and LF-4
each have a good expectation of permanence. However, for each of these alternatives, some risk
of contaminant rebound (after cleanup levels have been achieved) does exist, due to uncertainties
of contaminant flow in groundwater. Permanence of the groundwater remedial actions must be
evaluated over time (even following achievement of clean-up goals) to assess the ability to
sustain the cleanup goals once the remedial action is complete
Reduction of Toxicity, Mobility or Volume Through Treatment
Reduction of toxicity, mobility, or volume through treatment refers to the anticipated
performance of the treatment technologies that may be included as part of a remedy.
Treatment of the landfill waste or excavated brook sediments is not proposed or anticipated for
any of the LF alternatives. While mobility of contaminants is expected to be greatly reduced due
to the landfill cover system, this will not be accomplished through treatment.
Alternative LF-2a does not provide for active groundwater remediation unless the contingency
for active groundwater remediation is triggered. Active groundwater treatment (either extraction
and ex-situ or enhanced in-situ) is a component of alternatives LF-2b, LF-3 and LF-4, with LF-3
expected to provide the greatest reduction of toxicity and volume through treatment, due to
larger number of extraction wells, and volume of water to be extracted and treated. LF-2b
provides for active groundwater treatment at the Southern Lobe and monitored natural
attenuation at the Northern Lobe.
Short-Term Effectiveness
Short-term effectiveness addresses the period of time needed to implement the remedy and any-
adverse impacts that may be posed to workers and the community during construction and
operation of the remedy until cleanup goals are achieved.
No short-term impacts to the local community, on-site remedial workers or the environment will
occur under alternative LF-1. At the present time, South Street in Tewksbury is the only road
with access to the Site. Impacts from alternatives LF-2a, LF-2b, LF-3 and LF-4 to the local
community are expected to be significant due to the increased truck traffic during construction
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activities. Concerns about the potentially significant additional track traffic on South Street have
been vocalized by the community.
For the groundwater component of the alternative, the short-term impacts to the local
community, on-site remedial workers and the environment are anticipated to be slightly higher
for LF-3 due to the lengthier construction time and the larger impacts to the wetlands (during
extraction well and piping installation). Alternatives LF-2b and LF-4 are comparable for the
groundwater component of the remedy with LF-2a being lower assuming fewer
construction/installation components.
For the sediment/ brook component of the alternative, however, alternative LF-4 will provide the
highest short term impacts to the local community, on-site remedial works and the environment
compared to LF-2a, LF-2b and LF-3 due to the increased construction time and the increased
amount of resource area impacted during the brook filling and re-routing.
Implementabilitv
Implementability addresses the technical and administrative feasibility of a remedy from design
through construction and operation. Factors such as availability of services and materials,
administrative feasibility, and coordination with other governmental entities are also considered.
For the landfill final cover system, all of the alternatives are readily implementable, as they
require no construction (LF-1) or common construction activities (landfill final cover system)
that are straightforward to implement (LF-2 through LF-4). The presence of the wetland
resource areas and Sutton Brook surrounding the landfill lobes will present some challenges with
the design and construction; however, they are comparable for LF-2 through LF-4.
The groundwater component for alternative LF-I is easily implementable since no construction
activities are requireded to be implemented. Installation of the vertical barrier for LF-2 and LF-4
is a common construction activity, readily implementable; however, there may be some design
and construction challenges that will require coordination in conjunction with the final landfill
cover system design and construction due to the proximity of the brook and the edge of waste
(Southern Lobe). Installation of the groundwater extraction and treatment system for LF-3 is
straightforward; however, LF-3 has similar design and construction issues as LF-2 and LF-4 due
to the proximity of the edge of waste to the wetlands and brook. Detailed pre-design, pilot,
and/or bench scale studies will be required for LF-2b, LF-3, and LF-4 (and potentially LF-2a) to
allow effective design and implementation of the remedial action.
The brook sediment component of the landfill alternatives is straightforward and readily
implementable for LF-2 and LF-3; sediment removal and brook restoration with LF-2 and LF-3
will present significantly fewer challenges to implement than re-routing the brook with LF-4,
both in design and construction.
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All materials and services required for implementation are readily available either commercially
or via specialized vendors for all alternatives.
Cost
LF-1 $0
LF-2a $ 20,52 million
LF-2b $ 25.22 million
LF-3 $40.93-51.13 million
LF-4 $31.42 million
Note: The cost estimate for Alternative LF-2a assumes that MNA will be sufficient. The
estimated additional cost to implement the active groundwater contingency for Alternative LF-2a
is $4.7 million
Back-up information supporting the costs for these alternatives can be found in Appendix D of
the FS.
State Acceptance
The Commonwealth of Massachusetts has indicated its support for the selected remedy by
providing its concurrence in the attached letter (see Appendix A).
Community Acceptance
From June 28,2007 through July 28,2007, EPA held a public comment period to seek input
from the community regarding remedial cleanup alternatives evaluated for the Site. In addition
to written comments provided to EPA, comments were received during a Public Hearing held on
July 18, 2007.
Concern was expressed by many commenters regarding potential negative impacts from trucking
activities associated with all Landfill Lobes alternatives. The development and/or use of an
alternate route to access the site was urged. A summary of the comments received and EPA's
response to comments is included in the Responsiveness Summary portion of this ROD (Part 3).
2, Former Drum Disposal Area
Overall Protection of Human Health and the Environment
Overall protection of human health and the environment addresses whether each alternative
provides adequate protection of human health and the environment and describes how risks
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posed through each exposure pathway are eliminated, reduced, or controlled\ through treatment,
engineering controls, and/or institutional controls.
All of the alternatives, with the exception of FDD A-1, will be protective of human health and the
environment by eliminating, reducing, or controlling current and future risks through treatment,
containment and/or institutional controls.
Alternatives FDDA-2 through FDDA-5 all address current exposure risks through institutional
controls, restricting potable use of groundwater, soil removal or containment, and groundwater
remediation, until RAOs are attained. Groundwater RAOs will be attained with alternative
FDDA-4 using in-situ natural attenuation processes with a contingency for active groundwater
treatment and with alternatives FDDA-2, FDDA-3 and FDDA-5 through groundwater extraction
and ex-situ treatment.
For the impacted soils, alternative FDDA-2 utilizes a containment barrier (e.g. low permeability
cap) and institutional controls to control exposure. Alternatives FDDA-3 through FDDA-5 all
incorporate soil excavation to eliminate exposure risks associated with the impacted soils (as
well as eliminating the need for cap maintenance).
Compliance with Applicable or Relevant and Appropriate Requirements
Section 121(d) of CERCLA requires that remedial actions at CERCLA sites at least attain legally
applicable or relevant and appropriate Federal and State requirements, standards, criteria, and
limitations which are collectively referred to as "ARARs," unless such ARARs are waived under
CERCLA section 121(d)(4),
Applicable requirements are those substantive environmental protection requirements, criteria,
or limitations promulgated under Federal or State law that specifically address hazardous
substances, the remedial action to be implemented at the site, the location of the site, or other
circumstances present at the site. Relevant and appropriate requirements are those substantive
environmental protection requirements, criteria, or limitations promulgated
under Federal or State law which, while not applicable to the hazardous materials found at the
site, the remedial action itself, the site location or other circumstances at the site, nevertheless
address problems or situations sufficiently similar to those encountered at the site that their use
is well-suited to the site.
Compliance with ARARs addresses whether a remedy will meet all of the applicable or relevant
and appropriate requirements of other Federal and State environmental statutes or provides a
basis for invoking a waiver.
Alternative FDDA-1 will not meet chemical specific ARARs as no remedial actions will be
performed to reduce concentrations in soils and groundwater. The remaining alternatives can be
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designed to comply with chemical, location and action specific ARARs (summarized in
Appendix D and in Section 3 of the Feasibility Study), Attainment of chemical specific ARARs
with regard to groundwater will not occur immediately, but rather, over a period of time once
source control measures are implemented and in-situ or ex-situ treatment processes break down
contaminants. The estimated timeframe to achieve groundwater chemical specific ARARs for
alternatives FDDA-3, FDDA-4, and FDDA-5 are within the same order of magnitude (24 to 89
years for FDDA-3, 36 to 103 years for FDDA-4, and 23 to 85 years for FDDA-5) since the
source material is removed, with a differential of approximately 10 to 15 years between the
slowest and quickest alternatives primarily due to whether the groundwater component has active
treatment or MNA. Alternative FDDA-2 has a wider range in the estimated timeframe (30 to
134 years) to meet groundwater ARARs due to the uncertainty of timeframes for soil
contaminants to leach into groundwater. The alternatives that incorporate groundwater
extraction and ex-situ treatment with soil excavation (FDDA-3 and FDDA-5) were estimated to
meet cleanup goals in the quickest timeframe of approximately 23 to 89 years, but not
significantly quicker than FDDA-4 (36 to 103 years), which utilizes MNA,
Long-Term Effectiveness and Permanence
Long-term effectiveness and permanence refers to expected residual risk and the ability of a
remedy to maintain reliable protection of human health and the environment over time, once
clean-up levels have been met. This criterion includes the consideration of residual risk and the
adequacy and reliability of controls.
The three alternatives that incorporate soil excavation (FDDA-3, FDDA-4, and FDDA-5)
provide the highest level of long-term effectiveness and permanence, since the material is
removed from the area, preventing the potential for direct contact, as well as future leaching of
contaminants from soils to groundwater. Alternative FDDA-2 is effective in reducing risks
associated with the impacted soils; however, since the material remains in place, the long-term
effectiveness is reduced compared to FDDA-3, FDDA-4, and FDDA-5. Even with an
impermeable barrier, the potential exists for future leaching into groundwater since residuals
remain.
Alternatives FDDA-2 through FDDA-5 each prevent future potential risks via institutional
controls and various forms of remedial actions. Alternative FDDA-5 is the more aggressive
option as it extracts groundwater over the entire FDDA plume potentially resulting in a reduced
timeframe to achieve RAOs compared to the other FDDA alternatives (although modeling does
not demonstrate the potential advantage - FDDA-3 and FDDA-5 are both estimated to meet
cleanup goals in approximately 23-89 years). Alternatives FDDA-2 and FDDA-3 are similar to
FDDA-5 in that they involve groundwater extraction and treatment; however, the goal is
hydraulic containment/contaminant reduction. Because of this, in Alternatives FDDA-2 and
FDDA-3, groundwater is extracted only along the downgradient edge of the FDDA. Alternative
FDDA-4 capitalizes on existing natural attenuation processes occurring in this area with a
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contingency for active groundwater treatment to provide long-term effectiveness and
permanence.
Alternatives FDDA-2 through FDDA-5 all have a good expectation of permanence. However,
some risk of contaminant rebound (after cleanup levels have been achieved) does exist, due to
uncertainties of contaminant flow in groundwater. Permanence of the groundwater remedial
actions must be evaluated over time (even following achievement of clean-up goals) to assess the
ability to sustain the cleanup goals once the remedial action is complete.
Reduction of Toxicity, Mobility or Volume Through Treatment
Reduction of toxicity, mobility, or volume through treatment refers to the anticipated
performance of the treatment technologies that may be included as part of a remedy.
Treatment of impacted soils is not proposed for any of the FDDA alternatives. Therefore,
although mobility is expected to be greatly reduced by cover systems in all alternatives, this
reduction will not be achieved through treatment.
The toxicity and volume of contaminants in groundwater will be reduced for alternatives FDDA-
2, FDDA-3 and FDDA-5 through ex-situ treatment technologies, and the migration of
contaminants will be reduced via the groundwater extraction component of the treatment system.
FDDA-4 does not provide for active groundwater remediation unless the contingency for active
groundwater remediation is triggered. The contaminant mass destroyed in groundwater through
treatment will be comparable for alternatives FDDA-3 and FDDA-5. If the contingency for
active groundwater remediation is triggered, the contaminant mass destroyed in groundwater
through treatment in alternative FDDA-4 will be comparable to alternatives FDDA-3 and
FDDA-5. Since a larger contaminant mass will be present within the FDDA with alternative
FDDA-2 because no soil excavation would occur, this groundwater component will likely treat a
higher amount of mass during its operation when compared to FDDA-2, FDDA-3 and FDDA-5.
Short-Term Effectiveness
Short-term effectiveness addresses the period of time needed to implement the remedy and any
adverse impacts that may he posed to workers and the community during construction and
operation of the remedy until cleanup goals are achieved.
The three alternatives that incorporate soil excavation (FDDA-3, FDDA-4, and FDDA-5)
provide the highest level of short-term effectiveness since the material is removed from the area.
The short-term implementation impacts are anticipated to be slightly higher for FDDA-2,
FDDA-3 and FDDA-5. Due to the location of extraction wells and the need for access roads to
each well (access for O&M and for installation of extraction piping and electrical conduit),
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slightly higher impacts to the adjacent wetland resource area are anticipated. FDDA-5 will
require the most disruption/destruction, with FDDA-2 and FDDA-3 reduced, yet comparable to
one another.
The estimated timeframe to achieve RAOs for alternatives FDDA-3, FDDA-4, and FDDA-5 are
within the same order of magnitude since the source material is removed, with the quickest
timeframe estimated for FDDA-5, followed by FDDA-3. Alternative FDDA-2 has the potential
to be the lengthiest timeframe since infiltration is reduced (but not eliminated) through the cap.
Implementabilitv
Implementability addresses the technical and administrative feasibility of a remedy from design
through construction and operation. Factors such as availability of services and materials,
administrative feasibility, and coordination with other governmental entities are also considered.
For the soil component, all alternatives are easily implementable, requiring common construction
activities.
For the groundwater component, while FDDA-4 requires little construction when compared with
FDDA-2, FDDA-3 and FDDA-5, all alternatives can be implemented readily.
All materials and services required for implementation are readily available either commercially
or via specialized vendors for all alternatives.
Cost
FDDA-1 $0
FDDA-2 $ 7.53-8.33 million
FDDA-3 $ 7.62-9.22 million
FDDA-4 $2.81 million
FDDA-5 $ 9.93-12.33 million
Note: The cost estimate for Alternative FDDA-4 assume that MNA will be sufficient. The
estimated additional cost to implement the active groundwater contingency for Alternative
FDDA-4 is $4.5 million
Back-up information supporting the costs for these alternatives can be found in Appendix D of
the FS.
State Acceptance
The Commonwealth of Massachusetts has indicated its support for the selected remedy by
providing its concurrence in the attached letter (see Appendix A).
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Community Acceptance
From June 28, 2007 through July 28, 2007, EPA held a public comment period to seek input
from the community regarding remedial cleanup alternatives evaluated for the Site. In addition
to written comments provided to EPA, comments were received during a Public Hearing held on
July 18, 2007.
Comments were received in support of Alternative FDDA-4, as well as in support of FDDA-3
which has active groundwater treatment as a component. A summary of the comments received
and EPA's response to comments is included in the Responsiveness Summary portion of this
ROD (Part 3).
3. Garage and Storage Area
Overall Protection of Human Health and the Environment
Overall protection of human health and the environment addresses whether each alternative
provides adequate protection of human health and the environment and describes how risks
posed through each exposure pathway are eliminated, reduced» or controlled, through treatment,
engineering controls, and/or institutional controls.
Alternative GSA-1 (No Action) is the least protective of the two options as no action would be
taken to eliminate or control exposure risks. Potential future risks would remain and RAOs will
not be achieved. Alternative GSA-2 will effectively eliminate current and/or potential future
exposure risks as the material will be excavated and removed from the GSA.
Compliance with Applicable or Relevant and Appropriate Requirements
Section 121(d) of CERCLA requires that remedial actions at CERCLA sites at least attain legally
applicable or relevant and appropriate Federal and State requirements, standards, criteria, and
limitations which are collectively referred to as "ARARs, " unless such ARARs are waived under
CERCLA section 121(d)(4).
Applicable requirements are those substantive environmental protection requirements, criteria,
or limitations promulgated under Federal or State law that specifically address hazardous
substances, the remedial action to be implemented at the site, the location of the site, or other
circumstances present at the site. Relevant and appropriate requirements are those substantive
environmental protection requirements, criteria, or limitations promulgated
under Federal or State law which, while not applicable to the hazardous materials found at the
site, the remedial action itself the site location or other circumstances at the site, nevertheless
address problems or situations sufficiently similar to those encountered at the site that their use
is well-suited to the site.
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Compliance with ARARs addresses whether a remedy will meet all of the applicable or relevant
and appropriate requirements of other Federal and State environmental statutes or provides a
basis for invoking a waiver.
Alternative GSA-1 will not meet chemical specific ARARs as no remedial actions will be
performed to reduce contaminant concentrations in soils. Alternative GSA-2 can be designed to
comply with chemical, location and action specific ARARs.
Long-Term Effectiveness and Permanence
Long-term effectiveness and permanence refers to expected residual risk and the ability of a
remedy to maintain reliable protection of human health and the environment over time, once
clean-up levels have been met. This criterion includes the consideration of residual risk and the
adequacy and reliability of controls.
Through excavation and disposal beneath the landfill final cover system, alternative GSA-2 will
provide long term effectiveness and permanence as residual risks will be eliminated within the
GSA area.
Reduction of Toxicity. Mobility or Volume Through Treatment
Reduction of toxicity, mobility, or volume through treatment refers to the anticipated
performance of the treatment technologies that may be included as part of a remedy.
Treatment of the impacted soils is not proposed or anticipated for GSA-2.
Short-Term Effectiveness
Short-term effectiveness addresses the period of time needed to implement the remedy and any
adverse impacts that may be posed to workers and the community during construction and
operation of the remedy until cleanup goals are achieved.
The short-term impacts from Alternative GSA-2 are anticipated to be minimal and controllable
due to the relatively small volume of soils requiring removal, the short duration of construction
activity and the proximity to on-site disposal areas.
RAOs will be met for GSA-2 upon removal of the impacted soils, anticipated after 1 to 2 years
(includes timing for design, implementation, and confirmatory analysis).
Implementability
Implementability addresses the technical and administrative feasibility of a remedy from design
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through construction and operation. Factors such as availability of services and materials,
administrative feasibility, and coordination with other governmental entities are also considered.
GSA-2 is readily implementable. Soil excavation is a common technique, straight forward and
reliable to implement.
Cost
GSA-1 $0
GSA-2 $200,000
Back-up information supporting the costs for these alternatives can be found in Appendix D of
the FS.
State Acceptance
The Commonwealth of Massachusetts has indicated its support for the selected remedy by
providing its concurrence in the attached letter (see Appendix A).
Community Acceptance
From June 28, 2007 through July 28, 2007, EPA held a public comment period to seek input
from the community regarding remedial cleanup alternatives evaluated for the Site. In addition
to written comments provided to EPA, comments were received during a Public Hearing held on
July 18,2007.
A summary of the comments received and EPA's response to comments is included in the
Responsiveness Summary portion of this ROD (Part 3).
4. Downgradient Groundwater Area
Overall Protection of Human Health and the Environment
Overall protection of human health and the environment addresses whether each alternative
provides adequate protection of human health and the environment and describes how risks
posed through each exposure pathway are eliminated, reduced, or controlled, through treatment,
engineering controls, and/or institutional controls.
All of the alternatives, with the exception of DGGW-1, will be protective of human health and
the environment under this scenario by eliminating, reducing, or controlling current and future
risks through remedial actions and/or institutional controls.
Alternative DGGW-1 is the least protective of the four options as no action would be taken to
reduce concentrations in groundwater or to control exposure risks. Under this alternative, there
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would be no restrictions on groundwater use. The three remaining alternatives, DGGW-2,
DGGW-3, and DGGW-4, all address current exposure risks through institutional controls,
restricting potable use of groundwater in this area until RAOs are attained. Groundwater RAOs
will be attained with alternative DGGW-2 using in-situ natural attenuation processes (with a
contingency for an active treatment component based on the monitoring results) and with
alternatives DGGW-3 and DGGW-4 through groundwater extraction and ex-situ treatment.
Compliance with Applicable or Relevant and Appropriate Requirements
Section 121(d) of CERCLA requires that remedial actions at CERCLA sites at least attain legally
applicable or relevant and appropriate Federal and State requirements, standards, criteria, and
limitations which are collectively referred to as "ARARs, " unless such ARARs are waived under
CERCLA section 121(d)(4).
Applicable requirements are those substantive environmental protection requirements, criteria,
or limitations promulgated under Federal or State law that specifically address hazardous
substances, the remedial action to be implemented at the site, the location of the site, or other
circumstances present at the site. Relevant and appropriate requirements are those substantive
environmental protection requirements, criteria, or limitations promulgated
under Federal or Slate law which, while not applicable to the hazardous materials found at the
site, the remedial action itself, the site location or other circumstances at the site, nevertheless
address problems or situations sufficiently similar to those encountered at the site that their use
is well-suited to the site.
Compliance with ARARs addresses whether a remedy will meet all of the applicable or relevant
and appropriate requirements of other Federal and State environmental statutes or provides a
basis for invoking a waiver.
Alternative DGGW-1 will not meet chemical specific ARARs as no remedial actions will be
performed to reduce contaminant concentrations in groundwater. The remaining alternatives can
be designed to meet chemical, location, and action specific ARARs. Attainment of chemical
specific ARARs will not occur in the immediate short-term, but rather, over a period of time
once source control measures are implemented and in-situ or ex-situ treatment processes break
down contaminants. The estimated timeframe to achieve chemical specific ARARs for
alternatives DGGW-2 (67-79 years), DGGW-3 (57-68 years), and DGGW-4 (53-66 years) are
within the same order of magnitude.
Long-Term Effectiveness and Permanence
Long-term effectiveness and permanence refers to expected residual risk and the ability of a
remedy to maintain reliable protection of human health and the environment over time, once
clean-up levels have been met. This criterion includes the consideration of residual risk and the
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adequacy and reliability of controls.
Alternatives DGGW-2, DGGW-3, and DGGW-4 prevent future potential risks via institutional
controls and various forms of remedial aetions.
Alternative DGGW-4 is the most aggressive option as it extracts groundwater over the entire
DGGW plume, potentially resulting in a reduced time to achieve RAOs compared to the other
DGGW alternatives. Alternative DGGW-3 is similar to DGGW-4 in that it involves
groundwater extraction and treatment, but with fewer extraction wells and lower extraction rate.
Alternative DGGW-2 capitalizes on existing natural attenuation processes occurring in this area
and, with a contingency for active groundwater treatment based on the monitoring results,
provides long-term effectiveness and permanence.
As with the previous groundwater remedies, some risk of contaminant rebound (after cleanup
levels have been achieved), does exist, due to uncertainties of contaminant flow in groundwater.
Permanence of the groundwater remedial actions must be evaluated over time (even following
achievement of clean-up goals) to assess the ability to sustain the cleanup goals once the
remedial action is complete.
Reduction of Toxicity. Mobility or Volume Through Treatment
Reduction of toxicity, mobility, or volume through treatment refers to the anticipated
performance of the treatment technologies that may be included as part of a remedy.
DGGW-2 utilizes natural attenuation processes to address groundwater contamination and
therefore does not meet the treatment requirements for this criteria (unless the contingency for
active treatment is triggered). However, the processes will be permanent, with no treatment
residuals to handle. The toxicity and volume of contaminants in groundwater will be reduced for
alternatives DGGW-3 and DGGW-4 through ex-situ treatment technologies; the migration of
contaminants will be reduced via the groundwater extraction component of the treatment system.
The mass destroyed through treatment will be comparable for alternatives DGGW-3 and
DGGW-4, however, the timeframe to destroy the mass has been assumed to be expedited with
DGGW-4. It is anticipated that alternatives DGGW-3 and DGGW-4 will produce residuals
requiring off-site disposal (e.g. sludge from metals treatment) or treatment (e.g. carbon).
Short-T erm Effectiveness
Short-term effectiveness addresses the period of time needed to implement the remedy and any
adverse impacts that may be posed to workers and the community during construction and
operation of the remedy until cleanup goals are achieved.
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The short-term impacts to the local community and on-site remedial workers are anticipated to
be minimal for all alternatives. However, the impacts to the environment, specifically the
wetland resource area, from alternatives DGGW-3 and DGGW-4 are anticipated to be high.
With the installation of groundwater extraction wells throughout the DGGW area, destruction of
wetlands will be required to access, install, and maintain the groundwater extraction wells. In
addition, a gravel roadway (accessible by vehicle) will be required to each extraction point to
access the well and for installation of the extraction piping and utility conduits. With fewer
extraction wells, DGGW-3 will require significantly less destruction of the wetland resource area
(anticipated 5,050 sq ft) compared to DGGW-4 (anticipated 35,740 sq ft).
Impacts under DGGW-2 are anticipated to be minimal during installation of additional
monitoring wells and during monitoring activities. Access to wells during long-term monitoring
events can be on foot, not requiring access roads through the wetlands.
As discussed above, the estimated timeframe to achieve RAOs for alternatives DGGW-2 through
DGGW-4 are within the same order of magnitude. Through modeling, alternative DGGW-4 (53-
66 years) is anticipated to achieve RAOs quickest, followed by DGGW-3 (57-68 years) and then
DGGW-2 (67-79 years).
Implementabilitv
ImpkmentabiUty addresses the technical and administrative feasibility of a remedy from design
through construction and operation. Factors such as availability of services and materials,
administrative feasibility, and coordination with other governmental entities are also considered.
DGGW-2 is easily implementable since limited construction activities are required to be
implemented. As discussed above, installation of the groundwater extraction and treatment
systems for DGGW-3 and DGGW-4 will present potential construction issues, with access
concerns, destruction of wetlands, etc. Potential issues with discharging the treated groundwater
(due to excessive volume) may arise if one of these alternatives (DGGW-3 or DGGW-4) is
coupled with other high volume extraction rate alternatives (e.g. LF-3). The POTW or surface
water can handle the discharge from an individual alternative; however in the event that more
than one alternative requiring discharge is implemented, an evaluation will be required to
determine if one discharge method will be sufficient, or if a combination of discharge methods
will be required. Despite these issues, DGGW-3 and DGGW-4 are implementable.
All materials and services required for implementation are readily available either commercially
or via specialized vendors for all alternatives. None of the proposed alternatives should
significantly limit potential further remedial actions, if required.
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Cost
DGGW-1 SO
DGGW-2 $ 1.75 million
DGGW-3 $ 9.83-12.83 million
DGGW-4 $ 11.13-16.83 million
Note: The cost estimate for Alternative DGGW-2 assumes that MNA will be sufficient. The
estimated additional cost to implement the active groundwater contingency for Alternative
DGGW-2 is $2.5 million
Back-up information supporting the costs for these alternatives can be found in Appendix D of
theFS.
State Acceptance
The Commonwealth of Massachusetts has indicated its support for the selected remedy by
providing its concurrence in the attached letter (see Appendix A).
Community Acceptance
From June 28,2007 through July 28,2007, EPA held a public comment period to seek input
from the community regarding remedial cleanup alternatives evaluated for the Site. In addition
to written comments provided to EPA, comments were received during a Public Hearing held on
July 18, 2007.
A summary of the comments received and EPA's response to comments is included in the
Responsiveness Summary portion of this ROD (Part 3).
I,. THE SELECTED REMEDY
1. Summary of the Rationale for the Selected Remedy
The selected remedy is a comprehensive remedy which utilizes source control and management
of migration components to address the principal site risks.
The major components of the remedy include the following:
Excavation of contaminated soils exceeding site-specific cleanup levels from the
Former Drum Disposal Area (FDDA) and the former Garage and Storage Area
(GSA);
Excavation of contaminated soils and sediments exceeding site-specific cleanup
levels from a portion of Sutton Brook between the two landfill lobes;
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Consolidation of excavated soils and sediments along with other debris adjacent to
the landfills into the landfills;
Construction of a low permeability cap over both landfill lobes, including systems to
collect and manage gases and storm water from the landfills;
Construction of a vertical barrier to intercept groundwater from the southern landfill
lobe to prevent it from entering Sutton Brook;
Collection and treatment of contaminated groundwater from an area west of the
southern landfill lobe;
Monitored natural attenuation of areas of groundwater contamination not captured by
the extraction system, with a contingency to expand the area of active groundwater
remediation, if necessary;
Institutional controls such as deed restrictions and/or local ordinances to prevent
unacceptable exposures to wastes left in place and to restrict exposure to
contaminated groundwater until cleanup levels are met; and
Long-term groundwater, surface water, and sediment monitoring, and periodic five-
year review's of the remedy.
The capping and excavation components of the remedy will prevent direct contact with
contaminants by human and ecological receptors. In addition these components will prevent
migration of contaminants to groundwater and surface water.
The groundwater component of the remedy will prevent consumption of and exposure to
groundwater contaminants above site specific cleanup levels by human receptors. In addition,
the remedy will prevent recontamination of Sutton Brook and associated sediments.
2. Description of Remedial Components
The selected remedy is consistent with EPA's preferred alternative outlined in the June 2007
Proposed Plan and is consistent with a combination of all or a portion of Alternatives LF-2b,
FDDA-4, GSA-2, and DGGW-2, outlined in the June 2007 Feasibility Study. The selected
remedy is generally depicted in Figures L-l, L-2 and L-3.
Landfill Lobes - Alternative LF-2b
• Containment of Waste
The selected remedy includes capping of both the Northern and Southern Landfill Lobes with a
low permeability RCRA Subtitle C waste cover system. Prior to capping, miscellaneous debris
piles adjacent to the landfill will be consolidated into the area to be capped. Construction will
include grading the Landfill Lobes and installation of a low permeability RCRA (Resource
Conservation and Recovery Act) Subtitle C hazardous waste cover system over both Landfill
Lobes, totaling approximately 40 acres. The specific makeup of the cap layers will be
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determined during remedial design. It is expected, however, that, at a minimum, the cap will
include a gas vent layer, a HDPE geomembrane, drainage layer, and vegetative cover. In
addition, a landfill gas collection system, storm-water drainage structures (swales, rip-rap,
perimeter drains), and detention basins, as necessary, will be constructed as part of the remedy.
• Restoration of Wetlands and Brook
Contaminated sediments in Sutton Brook (between the Landfill Lobes) exceeding cleanup levels
will be excavated and consolidated into the Landfill Lobes. It is estimated that this would
involve excavation of approximately 750 cubic yards of contaminated sediments. Impacted
areas of the brook will be restored, including re-planting of appropriate vegetation. Precautions
will be taken to minimize the long-term impact to wetland areas as part of construction. Wetland
areas lost or impacted due to remediation of the brook and/or capping of the landfills will be
mitigated for in other areas of the Site.
• Partial Containment of Groundwater with a Vertical Barrier
A vertical barrier will be constructed along a portion of the Southern Lobe to limit the direction
of groundwater migration and to eliminate future impacts to Sutton Brook via groundwater
discharge. The barrier is estimated to be 1,700 linear feet with a depth of approximately 30 feet
below current grade. The type of impermeable vertical barrier (e.g., sheet pile, slurry wall, etc.)
will be determined during remedial design. Contaminated groundwater from the Southern Lobe
is currently discharging to Sutton Brook, or is initially migrating in a westerly direction and
discharging to Sutton Brook further downstream. The intent of the installation of this vertical
barrier is for groundwater contaminants to migrate towards the west and through the "Area for
Focused Groundwater Treatment," bringing high concentrations of additional contamination
through this area for subsequent treatment. In order to prevent migration of contaminated
groundwater under the vertical barrier, the base of the barrier will be "tied-in" to an
impermeable, or low-permeability layer (e.g., till or bedrock).
• Groundwater Remediation
The selected remedy calls for the extraction and treatment of groundwater at the Southern Lobe
at the "Area for Focused Groundwater Treatment" at the western limit of the vertical
containment barrier. Figure L-l shows the proposed locations for the vertical barrier and
groundwater collection/treatment. Due to the wide range of contaminants in groundwater,
further pre-design studies will be required to develop the precise combination of processes, but
they will likely include a combination of metals precipitation, UV-oxidation, carbon adsorption,
and/or air stripping. If appropriate, pre-design studies may also demonstrate that one or more
enhanced in-situ technologies may be effective. Cost estimates for this portion of the remedy
were based on the assumption that contaminated groundwater at the western/northwestern end of
the Southern Lobe will be intercepted by a series of groundwater extraction wells pumping at a
rate of 15 gallons per minute. The number of wells and the necessary pumping rate will be
determined during remedial design. Treated groundwater is expected to be discharged to the
local publicly owned treatment works (POTW); however, on-site discharge to Sutton Brook (or
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other on-site location) will be evaluated as part of remedial design. Design of the groundwater
component of this portion of the remedy will take into account the contingency for active
groundwater treatment outlined for other areas of the Site. That is, a single treatment plant may
be constructed with the ability to handle potential additional flows from potential future
extraction wells from other areas of the Site. As discussed earlier, groundwater at the Northern
Lobe exhibits significantly lower contaminant concentrations than groundwater at the Southern
Lobe. Because of the lower contaminant concentrations, monitored natural attenuation (MNA)
utilizing ongoing natural processes is the remedy for groundwater at the Northern Lobe.
• Institutional Controls
The remedy will also include institutional controls to prohibit landfill excavation, restrict the
future use of and access to the landfill, and restrict the future use of groundwater until remedial
goals are met. The type of institutional control(s) will be evaluated and selected during remedial
design. See Institutional Controls section below for additional information.
• Monitoring, Operation and Maintenance
The remedy will include monitoring of groundwater, surface water, landfill gas and leachate;
monitoring of wetlands to determine the success of wetlands mitigation and restoration; as well
as operation and maintenance activities for each component of the remedy (cap repairs, mowing,
groundwater treatment plant operation, etc.). See also Long Term Monitoring and Five-Year
Reviews section below.
The Landfill Lobes portion of the remedy will achieve RAOs by: capping the waste to prevent
contact, surface water runoff, and leaching; preventing exposure to contaminated groundwater by
actively treating some groundwater, removing contamination sources and addressing other
groundwater through MNA; and preventing the migration of groundwater contamination to
Sutton Brook surface water and sediments, by the installation of a vertical barrier.
The total cost of the Landfill Lobes portion of the remedy is $25.22 million.
Former Drum Disposal Area - Alternative FDDA-4
• Excavation, Treatment and/or Disposal of Soils
As part of the selected remedy, soils (approximately 8,900 cubic yards) contaminated in excess
of site-specific cleanup levels will be excavated and consolidated into the landfill lobes prior to
lobe capping. If it is determined to be more cost-effective, these soils may also be disposed of at
an appropriate off-site facility. Removal of the remaining source material will eliminate future
leaching into groundwater and expedite the timeframe to meet groundwater cleanup levels. A
conceptual plan is shown in Figure L-2. Excavated areas will be restored with clean fill.
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• Groundwater Remediation (Focused Mass Reduction)
The selected remedy will address groundwater contamination in this area through natural
attenuation processes. Upon completion of source area remedial measures (FDDA excavation), a
monitored natural attenuation (MNA) program will be initiated. As discussed earlier, analytical
and geochemical data have indicated that natural attenuation processes are occurring within and
downgradient of the source areas, These natural in-situ attenuation processes include
biodegradation, dispersion, dilution, adsorption, volatilization, and chemical or biological
stabilization, transformation, or destruction of contaminants. Groundwater modeling predicts
that the time needed to achieve RAOs using MNA is comparable to other alternatives.
Groundwater flow, geochemistry, contaminant distribution and migration will be monitored. See
also Lone Term Monitoring and Five-Year Reviews section below. The selected remedy also
includes a contingency for implementation of active groundwater remediation (extraction and
treatment or an enhanced in-situ technology), if necessary.
Once the source control measures are implemented, monitoring will be performed to determine
the resulting flow regime, as well as to evaluate, on an ongoing basis, contaminant levels and
whether existing site conditions continue to support the use of MNA to address groundwater
RAOs. The purpose of the monitoring program is to:
• Demonstrate that natural attenuation is occurring according to expectations;
. Detect changes in environmental conditions that may reduce the efficacy of any natural
attenuation processes;
• Identify any potentially toxic and/or mobile transformation products;
• Verify that the plume is not expanding;
• Verify that there are no unacceptable impacts to downgradient receptors;
• Detect any new releases of contaminants to the environment that could impact the
effectiveness of the natural attenuation remedy; and
• Verify attainment of remedial objectives.
Groundwater will be monitored on a quarterly basis for a minimum of five years for the purpose
of monitoring and evaluating the MNA portion of the remedy. After five years, EPA will
determine if quarterly monitoring of groundwater remains necessary or if a different interval is
appropriate for monitoring groundwater.
EPA will evaluate the progress of the MNA portion of the remedy toward achieving RAOs as
data become available, but no less frequently than during the 5-Year Reviews conducted for the
Site. The following criteria are among those which will be considered to determine whether
MNA continues to be the appropriate remedy to address groundwater contamination:
• Contaminant concentrations in groundwater at specified locations exhibit an increasing
trend not originally predicted during remedy selection;
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• Near-source wells exhibit large concentration increases indicative of a new or renewed
release;
• Contaminants are identified in monitoring wells located outside of the original plume
boundary;
• Contaminant concentrations are not decreasing at a sufficiently rapid rate to meet the
remediation objectives; and
• Changes in land and/or groundwater use will adversely affect the protectiveness of the
MNA remedy.
If EPA determines that MNA is no longer an appropriate remedy to effectively achieve
groundwater RAOs, a contingent remedy involving the extraction and treatment of groundwater
will be designed and implemented.
If a groundwater extraction and treatment system is implemented, extracted groundwater would
either be directed to the treatment plant constructed as part of Landfill Lobes portion of the
remedy or to a second treatment plant designed along the same parameters as outlined in the
Landfill Lobes portion of the remedy above.
• Institutional Controls
The remedy will also include institutional controls to restrict the future use of groundwater until
remedial goals are met. The type of institutional control(s) will be evaluated and selected during
remedial design. See Institutional Controls section below for additional information.
• Monitoring; Operation and Maintenance
The remedy will include long-term monitoring of groundwater. Monitoring will continue at least
until groundwater RAOs are attained. Operation and maintenance activities would also be
required should the contingent remedy be implemented.
The FDDA portion of the remedy will achieve RAOs by: removing the contamination source
material to prevent direct contact/ingestion/inhalation of residual levels of contaminants in soils
as well as preventing leaching of contaminants from soils to groundwater; and utilizing MNA
processes to address groundwater contamination. If monitoring criteria determine that MNA is
not adequate, active groundwater remediation will be implemented.
The cost of the FDDA portion of the remedy is $2,81 million.
The estimated additional cost to implement the active groundwater contingency for the FDDA is
$4.5 million.
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Garaee and Storage Area - Alternative GSA-2
• Soil Excavation and Disposal
The selected remedy calls for excavation of soils contaminated in excess of site-specific risk-
based cleanup levels (approximately 530 cubic yards) and consolidation in the Landfill Lobes
prior to lobe capping. If it is determined to be more cost-effective, these soils may also be
disposed of at an appropriate off-site facility. A conceptual excavation plan is shown in Figure
L-2. Excavated areas will be restored with clean fill.
The GSA portion of the remedy achieves RAOs by excavating and removing the contaminated
soils.
Monitoring, Operation and Maintenance, and Institutional Controls will not be necessary at the
Garage and Storage Area.
The cost of the GSA portion of the remedy is $ 200,000.
Downeradient Groundwater - Alternative DGGW-2
• In-Situ Remediation
Groundwater contamination will be addressed through natural attenuation processes with a
contingency for active groundwater treatment if necessary in the future. Based upon the source
control remedies and the groundwater remediation outlined for other areas of the Site, active
groundwater extraction and treatment in the downgradient groundwater portion of the plume will
not be included as part of the initial remedy. As discussed earlier, analytical and geochemica!
data have indicated that natural attenuation processes are occurring within and downgradient of
the source areas. These natural in-situ attenuation processes include biodegradation, dispersion,
dilution, adsorption, volatilization, and chemical or biological stabilization, transformation, or
destruction of contaminants. Groundwater modeling predicts that the time needed to achieve
RAOs using MNA is comparable to other alternatives. Groundwater flow, geochemistry,
contaminant distribution and migration will be monitored. See also Long Term Monitoring and
Five-Year Reviews section below. The selected remedy also includes a contingency for
implementation of active groundwater remediation (extraction and treatment or an enhanced in-
situ technology), if necessary.
Once the source control measures are implemented, monitoring will be performed to determine
the resulting flow regime, as well as to evaluate, on an ongoing basis, contaminant levels, and
whether existing site conditions continue to support the use of MNA to address groundwater
RAOs. The purpose of the monitoring program is to:
• Demonstrate that natural attenuation is occurring according to expectations;
• Detect changes in environmental conditions that may reduce the efficacy of any natural
attenuation processes;
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• Identify any potentially toxic and/or mobile transformation products;
• Verify that the plume is not expanding;
• Verify that there are no unacceptable impacts to downgradient receptors;
• Detect any new releases of contaminants to the environment that could impact the
effectiveness of the natural attenuation remedy; and
• Verify attainment of remedial objectives.
Groundwater will be monitored on a quarterly basis for a minimum of five years for the purpose
of monitoring and evaluating the MNA portion of the remedy. After five years, EPA will
determine if quarterly monitoring of groundwater remains necessary or if a different interval is
appropriate for monitoring groundwater.
EPA will evaluate the progress of the MNA portion of the remedy toward achieving RAOs as
data become available, but no less frequently than during the 5-Year Reviews conducted for the
Site. The following criteria are among those which will be considered to determine whether
MNA continues to be the appropriate remedy to address groundwater contamination;
• Contaminant concentrations in groundwater at specified locations exhibit an increasing
trend not originally predicted during remedy selection;
• Near-source wells exhibit large concentration increases indicative of a new or renewed
release;
• Contaminants are identified in monitoring wells located outside of the original plume
boundary;
• Contaminant concentrations are not decreasing at a sufficiently rapid rate to meet the
remediation objectives; and
• Changes in land and/or groundwater use will adversely affect the protectiveness of the
MNA remedy.
If EPA determines that MNA is no longer an appropriate remedy to effectively achieve
groundwater RAOs, a contingent remedy involving the extraction and treatment of groundwater
will be designed and implemented.
If EPA determines in the future that active groundwater extraction and treatment are necessary, it
is estimated that contaminated groundwater could be captured by a series of three extraction
wells pumping at a combined rate of 75 gpm. It is likely that, should this contingency need to be
implemented, extracted groundwater would be treated in a separate treatment plant using similar
parameters as outlined in the Landfill Lobes portion of the remedy above. However, a
cost/benefit analysis will be conducted as part of the remedial design for the Landfill Lobes
portion of the remedy to consider the relative merits of designing that treatment plant to handle
potential future flows from the FDDA and DGGW. For purposes of estimating costs, only the
monitored natural attenuation remedy for this area of the Site is included.
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• Institutional Controls
The remedy will also include institutional controls to restrict the future use of groundwater until
remedial goals are met. The type of institutional control(s) will be evaluated and selected during
remedial design. See Institutional Controls section below for additional information.
• Monitoring, Operation and Maintenance
The remedy will include long-term monitoring of groundwater at least until RAOs are attained.
Operation and maintenance activities would also be required should the contingent remedy be
implemented.
The DGGW portion of the remedy will achieve RAOs by utilizing MNA processes to address
groundwater contamination. If monitoring criteria determine that MNA is not adequate, active
groundwater remediation will be implemented.
The cost of the DGGW portion of the remedy is $1.75 million.
The estimated additional cost to implement the active groundwater contingency for the DGGW
is $2.5 million.
The total estimated cost of the Sutton Brook Disposal Area remedy is $29.98 million. As
discussed earlier, the cost of the active groundwater contingencies are FDDA - $ 4.5 million, and
DGGW - $2.5 million, for a total of $7 million. If both contingencies are implemented, the total
estimated cost of the Sutton Brook Disposal Area remedy is $36.98 million.
The selected remedy may change somewhat as a result of the remedial design and construction
processes. Changes to the remedy described in this Record of Decision, if any, will be
documented in an Explanation of Significant Differences, or a Record of Decision Amendment,
as appropriate.
Institutional Controls
In order to protect human health by controlling potential exposures to contaminated soils,
sediments, and groundwater, the selected remedy relies on the use of Institutional Controls such
as limitations on land and groundwater uses and activities. Institutional Controls are also
necessary for the protection of the selected remedy. The details of the institutional controls will
be resolved during the pre-design and remedial design phase in coordination with the parties
performing the remedial action, impacted landowners, and local officials. MassDEP's
participation with the Institutional Controls will be in accordance with Commonwealth of
Massachusetts policies, guidance and regulations.
Risks from exposure to contaminated groundwater will be controlled through the implementation
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of institutional controls. In areas where groundwater contamination exceeds cleanup levels,
groundwater use restrictions will be required for drinking water, industrial process water, or
other purposes, until groundwater cleanup levels are met. The institutional controls pertaining to
groundwater will include a local Town ordinance and/or moratorium that would be put in place
under and within 500 feet of the edge of the mapped groundwater plume, or a Grant of
Environmental Restriction. Other institutional controls mechanisms may be required, including
Notices of Activity and Use Limitations. Institutional Controls will also be required to ensure
that any remedial components constructed as part of the selected remedy, such as the landfill
caps, are not disturbed or otherwise compromised by any other use or activity. Those
implementing the ICs would be responsible to work with the Towns and affected property
owners to help put in place these restrictions.
Institutional controls on groundwater are expected to be temporary (with the exception of under
the Landfill Lobes), until such time as groundwater cleanup goals are met. Therefore, as the areal
extent of contamination in the aquifer decreases, the area impacted by these restrictions will also
change (decrease). Therefore periodic re-evaluation of the area impacted the ICs will be
performed and the restrictions may change accordingly.
Long-term Monitoring and Five-year Reviews
Long-term monitoring of groundwater, surface water, and sediments will be required in order to
evaluate contaminant status and migration and performance of the selected remedy.
Groundwater monitoring is included to ensure that the remedy, as constructed, is operating as
intended and to evaluate the success of MNA processes and to evaluate the need for
implementation of the contingency remedy. Details of the monitoring program will be further
developed during design and the preparation of a long-term monitoring plan.
Since wastes will be left in place as part of the selected remedy, the NCP requires periodic
reviews of the remedy. A comprehensive review will be conducted at least every five years to
evaluate the protectiveness of the remedy. The purpose of this Five-year Review is to evaluate
the implementation and performance of the remedy in order to determine if the remedy is or will
be protective of human health and the environment. The Five-year Review will document
recommendations and follow-up actions as necessary to ensure long-term protectiveness of the
remedy or bring about protectiveness of a remedy that is not protective. These recommendations
could include providing additional response actions, improving O&M activities, optimizing the
remedy, enforcing access controls and institutional controls and conducting additional studies
and investigations.
The selected remedy also includes long-term operation, inspections, and maintenance of any
systems put in place as part of the remedy, including the landfill caps, landfill gas and leachate
collection systems, and systems to intercept, collect and treat contaminated groundwater. Long-
term inspections and monitoring will also be required to ensure that institutional controls remain
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effective and are being enforced, and, long-term monitoring of groundwater, surface water,
sediments and biota will be necessary to evaluate the effectiveness and re-colonization of biota in
excavated areas of Sutton Brook, as well as the effectiveness of any revegetation, wetland
restoration, or wetland replication area.
3. Summary of the Estimated Remedy Costs
Landfill Lobes
LF-2b: Containment of waste, vent landfill gas, restoration of wetlands and brook,
partial containment of groundwater with a vertical barrier and groundwater
remediation
CAPITAL COSTS LF-2b
Construction Activities
Pilot and Pump Test
$50,000
Site Prep
$90,000
Site Work
$44,800
LF Containment
$10,161,000
Sediment Excavation/ Brook Restoration
$1,046,620
Groundwater Containment
$1,785,000
In-situ groundwater remediation - MNA
$51,000
Groundwater extraction and ex-situ treatment
$1,582,000
Institutional Controls
$50,000
SUBTOTAL-CONSTRUCTION ACTIVITIES $14,910,420 -
Contingency 110%) $1,491,100
TOTAL CONSTRUCTION ACTIVITIES $16,401,520
Professional/ Technical Services
Project Management $820,100
Remedial Design
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$984,100
Construction Management $984,100
Health and Safely $246,100
Permitting/ Legal $246,100
TOTAL PROFESSIONAL/ TECHNICAL SERVICES $3,280,500
TOTAL CAPITAL COSTS $19,682,020
¦ * r — 1 1 ••• *
ANNUAL OPERATION, MAINTENANCE AND MONITORING COSTS
LF-2b - GROUNDWATER MONITORING - 3 YEARS, GROUNDWATER
EXTRACTION, TREATMENT AND MONITORING - 27 YEARS $5,353,000
TOTAL- PRESENT VALUE - QAM COSTS $5,353,000
PERIODIC COSTS - PRESENT VALUE (7%)
Five Year Site Reviews $43,000
Groundwater Performance and Optimization Study $11,000
Remedial Action Report $21,000
Demobilization of on-site treatment system $20,000
Well Abandonment $13,000
Update institutional Controls Plan $7,000
TOTAL PRESENT VALUE PERIODIC COSTS $118,000
TOTAL PRESENT VALUE $25,150,020
• —
LF-2b
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Former Drum Disposal Area
FDDA-4: Excavation, treatment and/or disposal of soils with groundwater remediation (focused mass
reduction)
CAPITAL COSTS
Construction Activities
Perform groundwater pilot test, data analysis
$50,000
-
Site Prep
$52,500
-
Site Work
$6,300
-
Soil Excavation
$333,300
-
In-situ groundwater treatment - MNA
$38,000
On-site Disposal
$222,500
-
Groundwater Containment Extraction and Treatment System
$
-
Institutional Controls
$20,000
-
SUBTOTAL - CONSTRUCTION ACTIVITIES
$722,600
-
Contingency (10%)
$72,300
-
TOTAL CONSTRUCTION ACTIVITIES
$794,900
-
Profesional/ Technical Services
4
Project Management
$47,700
- $
<
Remedial Design
$95,400
Construction Management
$63,600
*
- S
*
Health and Safety
$23,900
Permitting/ Legal
$23,900
*
- i
TOTAL PROFESSIONAL/ TECHNICAL SERVICES
$254,500
* w
TOTAL CAPITAL COSTS
$1,049,400
- $
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ANNUAL OPERATION, MAINTENANCE AND MONITORING COSTS
MNA-30 YEARS
$1,706,000
TOTAL - PRESENT VALUE - MNA COSTS
$1,706,000
• $
TOTAL - PRESENT VALUE-0 AM COSTS
$1,706,000
$
PERIODIC COSTS - PRESENT VALUE (7%)
Five Year Site Reviews
$43,000
Groundwater Performance and Optimization Study
$11,000
Remedial Action Report
$21,000
Demobilization of on-site treatment system
$20,000
Well Abandonment
Update Institutional Controls Plan
$13,000
$3,000
TOTAL PRESENT VALUE PERIODIC COSTS
$111,000
TOTAL PRESENT VALUE
$2,866,400
The estimated additional cost to implement the active groundwater contingency for the
FDDA is $4.5 million.
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Garage and Storage Area
GSA-2: Excavation and on-site disposal of soils
CAPITAL COSTS
Construction Activities
Pre-implementation Monitoring, Sampling, Testing and Analysis
$22,400
Mobilization/Demobilization
$30,000
Site Prep
$2,600
Soil Excavation
$52,000
On-site Disposal
Institutional Controls
$13,300
$
SUBTOTAL - CONSTRUCTION ACTIVITIES - ON-SITE DISPOSAL
$120,300
ConUugency(10%)
$12,100
TOTAL CONSTRUCTION ACTIVITIES
$132,400
Profesional/ Technical Services
Project Management
$10,600
Remedial Design
$19,900
Construction Management
$13,300
Health and Safety
$4,000
Permitting/ Legal
$4,000
TOTAL PROFESSIONAL/ TECHNICAL SERVICES
$51,800
TOTAL CAPITAL COSTS
$184,200
ANNUAL OPERATION AND MAINTENANCE COSTS
O&M SUBTOTAL; $
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Contingency (10%)
TOTAL - O&M COSTS (ANNUAL)
$
$
TOTAL-PRESENTVALUE
S
PERIODIC COSTS - PRESENT VALUE (7%)
Five Year Site Reviews
Groundwater Performance and Optimization Study
$
$
Remedial Action Report
Demobilization of on-site treatment system
Well Abandonment
Update Institutional Controls Plan
$16,000
$
$
$
$
TOTAL PRESENT VALUE - PERIODIC COSTS
$16,000
TOTAL PRESENT VALUE
$200,200
Note: Costs assume no treatment prior to on-site disposal.
Downeradient Groundwater Area
DGGW-2: In-sftu Remediation (Assumes30yearn ofMNA)
CAPfTAL COSTS
Construction Activities
Mobilization/Demobilization $42,500
In-situ groundwater treatment - MNA $88,500
Institutional Controls $20,000
SUBTOTAL - CONSTRUCTION ACTIVmES $ 151,000
Contingency (10%) $15,100
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TOTAL CONSTRUCTION ACTIVITIES $166,100
Profesional/ Technical Services
Project Management $12,100
Remedial Design $22,700
Construction Management $15,100
Health and Safety $4,600
Permitting/ Legal $4,600
TOTAL PROFESSIONAL/ TECHNICAL SERVICES $59,100
TOTAL CAPITAL COSTS $225,200
ANNUAL OPERATION, MAINTENANCE AND MONITORING COSTS
GroundwaterTreatment- MNA $93,800
Annual site-wide Inspection $3,000
O&M SUBTOTAL: $101,800
Contingency (10%) $10,200
TOTAL-0&M COSTS (ANNUAL) $112,000
TOTAL - PRESENT VALUE • 30 YEARS, 7% $1,389,900
(30 YR)
PERIODIC COSTS - PRESENT VALUE (7%)
Five YearSite Reviews $43,000
Groundwater Performance and Optimization Study $38,000
Remedial Action Report $26,000
Demobilization of on-site treatment system $
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Well Abandonment $7,000
Update Institutional Controls Plan $3,000
TOTAL PRESENT VALUE ¦ PERIODIC COSTS
$117,000
TOTAL PRESENT VALUE
$1,732,100
The estimated additional cost to implement the active groundwater contingency for the
DGGW is $2.5 million.
The information in this cost estimate summary tabic is based on the best available information
regarding the anticipated scope of the remedial alternative. Changes in the cost elements are
likely to occur as a result of new information and data collected during the engineering design of
the remedial alternative. Major changes may be documented in the form of a memorandum in the
Administrative Record file, an ESD, or a ROD amendment. This is an order-of-magnitude
engineering cost estimate that is expected to be within +50 to -30 percent of the actual project
cost.
4, Expected Outcomes of the Selected Remedy
The primary expected outcomes of the selected remedy are that: groundwater throughout
the Site beyond the point of compliance (the edge of the Landfill Lobes) will no longer present
an unacceptable risk to future residents or future facility workers via ingestion or inhalation and
will be suitable for consumption; presumed risk from contact with landfill waste will be
eliminated; ongoing impacts to groundwater from landfill waste, will be reduced or eliminated;
the soils at the Site (Garage and Storage Area) will no longer present an unacceptable risk to
future residents via direct contact and will be suitable for general use; and soils at the Site
(Former Drum Disposal Area) will no longer be a source of groundwater contamination.
Approximately 65-210 years are estimated as the amount of time necessary to achieve the goal of
groundwater acceptable for human consumption, and 2-3 years are estimated as the amount of
time necessary to achieve the soil goals at the Garage and Storage Area and the Former Drum
Disposal Area. The selected remedy will also provide environmental and ecological benefits
such as restoration of impacted brook sediments and surface water, and protection of terrestrial
and aquatic wildlife.
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a. Cleanup Levels
i. Ground Water Cleanup Levels
Cleanup levels have been established in groundwater for all chemicals of concern
identified in the Baseline Risk Assessment found to pose an unacceptable risk to either public
health or the environment. Cleanup levels have been set based on the ARARs (MCLs) as
available, or other suitable criteria described below. Periodic assessments of the protection
afforded by remedial actions will be made as the remedy is being implemented and at the
completion of the remedial action. At the time that Ground Water Cleanup Levels identified in
the ROD and newly promulgated ARARs and modified ARARs which call into question the
protectiveness of the remedy have been achieved and have not been exceeded for a period of
three consecutive years, a risk assessment shall be performed on all residual groundwater
contamination to determine whether the remedial action is protective. This risk assessment of
the residual groundwater contamination shall follow EPA procedures and will assess the
cumulative carcinogenic and non-carcinogenic risks posed by all chemicals of concern
(including but not limited to the chemicals of concern) via ingestion of groundwater and
inhalation of VOCs from domestic water usage. If, after review of the risk assessment, the
remedial action is not determined to be protective by EPA, the remedial action shall continue
until either protective levels are achieved, and are not exceeded for a period of three consecutive
years, or until the remedy is otherwise deemed protective or is modified. These protective
residual levels shall constitute the final cleanup levels for this ROD and shall be considered
performance standards for this remedial action.
Because the aquifer at and beyond the compliance boundary for the landfill is a Class IIB
aquifer which is a potential source of drinking water, MCLs established under the Safe Drinking
Water Act, are ARARs. The Massachusetts Department of Environmental Protection completed
a Ground Water Use and Value Determination on the aquifer in which the Sutton Brook Disposal
Area Site is located. This determination is attached as Appendix B. This finding indicates that
the groundwater beneath the Site has medium use and value as a future drinking water supply
because the aquifer is considered to be a potential source of drinking water, and there are several
private well users in the area (private wells do not appear to have been impacted by the Site).
Therefore, drinking water standards, consistent with the use and value determination, shall be
required to be attained in the groundwater at the Site.
In the absence of an MCLG, an MCL, a proposed MCLG, proposed MCL, a more
stringent State standard, or other suitable criteria to be considered (i.e., health advisory, State
guideline), a cleanup level was derived for each chemical of concern having carcinogenic
potential (Classes A, B, and C compounds) based on a 10"6 excess cancer risk level per
compound considering the future ingestion of ground water and inhalation of VOCs from
domestic water usage. In the absence of the above standards and criteria, cleanup levels for all
other chemicals of concern (Classes D and E) were established based on a level that represent an
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acceptable exposure level to which the human population including sensitive subgroups may be
exposed without adverse affect during a lifetime or part of a lifetime, incorporating an adequate
margin of safety (hazard quotient = 1) considering the future ingestion of groundwater and
inhalation of VOCs from domestic water usage.
Table L-l summarizes the Cleanup Levels for carcinogenic and non-carcinogenic
chemicals of concern identified in ground water.
All Groundwater Cleanup Levels identified in the ROD and newly promulgated ARARs
and modified ARARs which call into question the protectiveness of the remedy and the
protective levels determined as a consequence of the risk assessment of residual contamination,
must be met at the completion of the remedial action at the points of compliance. At this Site,
Groundwater Cleanup Levels must be met at the edge of and beyond the Landfill Lobes (this
includes groundwater at the Former Drum Disposal Area, and the Down gradient Groundwater
Area). EPA has estimated that the Cleanup levels will be obtained within 65-210 years after
completion of the source control component.
After the cleanup levels have been met at the Former Drum Disposal Area, the Downgradient
Groundwater Area, and at the downgradient edge of the Landfill Lobes, and the remedy is
determined to be protective, the groundwater treatment system will be shut down. The
groundwater monitoring system will be utilized to collect information quarterly for three
additional years to ensure that the cleanup levels have been met and the remedy is protective.
ii. Soil Cleanup Levels
Human Health Based Soil Cleanup Levels
Soil cleanup levels for compounds of concern in soils at the Garage and Storage Area
exhibiting an unacceptable cancer risk have been have been established such that they are
protective of human health. Soil cleanup levels for known and suspect carcinogenic chemicals
of concern (Classes A, B, and C compounds) have been set at a 10"5 excess cancer risk level
considering exposure of future residents (adult and young child) to upland soils (by ingestion and
dermal contact) at the Garage and Storage Area. Exposure parameters for ingestion and dermal
contact have been described in Section G. If a cleanup value described above is not capable of
being detected with good precision and accuracy or is below background values, then either the
practical quantitation limit or a background value was used as appropriate for the soil cleanup
level.
Table L-2 summarizes the cleanup levels for carcinogenic and non-carcinogenic
chemicals of concern in soils protective of direct contact with soils.
These cleanup levels must be met at the completion of the remedial action at the Garage
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and Storage Area. These soil cleanup levels attain EPA's risk management goal for remedial
actions and have been determined by EPA to be protective.
- Ecological Based Soil Cleanup Levels
Soil cleanup levels for chemicals of concern in soils at the Garage and Storage Area and
the Former Drum Disposal Area exhibiting an unacceptable ecological risk, have been
established such that they are protective of terrestrial wildlife. Exposure parameters and
assumptions utilized to develop these cleanup levels have been described in Section G.
Table L-3 summarizes the cleanup levels for ecological chemicals of concern in soils
protective of terrestrial wildlife.
These cleanup levels must be met at the Garage and Storage Area and the Former Drum
Disposal Area. These soil cleanup levels attain EPA's risk management goal for remedial
actions and have been determined by EPA to be protective.
EPA also considered the potential for contaminants in soils at the FDDA to continue to
be a source of groundwater contamination. Chemicals detected in both soils and groundwater
were compared. The comparison showed that twenty-eight chemicals were found in both soils
and groundwater. Of the chemicals found in both soils and groundwater, seventeen have SSLs
(Soil Screening Levels, EPA 2002). Of these seventeen chemicals, arsenic, bis(2-
Ethylhexyl)phthalate, ethyl benzene, toluene and xylenes exceed MCLs in groundwater. A soil
cleanup level has not been set for arsenic, as arsenic soil exposures did not exceed EPAs risk
range. Furthermore, arsenic in soils was detected at the FDDA at concentrations which are lower
than the level that would be set to address the potential for leaching. For the other four organic
chemicals (bis(2-Ethylhexyl)phthalate, ethylbenzene, toluene and xylenes), the soil cleanup
levels which have been set to address ecological risk will also be protective of potential leaching
to groundwater.
iii. Surface Water Cleanup Levels
Cleanup levels for chemicals of concern in surface water between the landfill lobes
exhibiting an unacceptable ecological risk, have been established such that they are protective of
aquatic life. Exposure parameters and assumptions utilized to develop these cleanup levels have
been described in Section G.
Table L-4 summarizes the cleanup levels for ecological chemicals of concern in surface
water protective of aquatic life.
These cleanup levels must be met at the completion of the remedial action at within
Sutton Brook. These surface water cleanup levels attain EPA's risk management goal for
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remedial actions and have been determined by EPA to be protective,
iv. Sediment Cleanup Levels
Cleanup levels for chemicals of concern in sediments between the landfill lobes
exhibiting an unacceptable ecological risk, have been established such that they are protective of
aquatic life. Exposure parameters and assumptions utilized to develop these cleanup levels have
been described in Section G.
Table L-5 summarizes the cleanup levels for ecological chemicals of concern in
sediments protective of aquatic life.
These cleanup levels must be met at the completion of the remedial action within the
Sutton Brook channel. These sediment cleanup levels attain EPA's risk management goal for
remedial actions and have been determined by EPA to be protective.
These soil, surface water and sediment cleanup levels must be met at the completion of the
remedial action at the points of compliance. They are consistent with ARARs for soils, surface
water and sediments, attain EPA's risk management goals for remedial action, and are protective
of human health or the environment.
M. STATUTORY DETERMINATIONS
The remedial action selected for implementation at the Sutton Brook Disposal Area Site is
consistent with CERCLA and, to the extent practicable, the NCP. The selected remedy is
protective of human health and the environment, will comply with ARARs and is cost effective.
In addition, the selected remedy utilizes permanent solutions and alternate treatment technologies
or resource recovery technologies to the maximum extent practicable, and satisfies the statutory
preference for treatment that permanently and significantly reduces the mobility, toxicity or
volume of hazardous substances as a principal element.
1. The Selected Remedy is Protective of Human Health and the Environment
The remedy at this Site will adequately protect human health and the environment by
eliminating, reducing or controlling exposures to human and environmental receptors through
treatment, engineering controls and institutional controls. More specifically:
At the Landfill Lobes: the cap will prevent direct contact with the waste and infiltration of
contaminants to groundwater; the vertical barrier will prevent recontamination of Sutton Brook
by controlling migration of contaminated groundwater; active treatment of groundwater and
MNA will help restore the aquifer; institutional controls will protect the remedy and prevent use
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of contaminated groundwater; and excavation/restoration of wetlands will eliminate risk to
wildlife receptors.
At the Former Drum Disposal Area: Excavation of soils will remove an ongoing source of
groundwater contamination and will eliminate risk from soil exposure to terrestrial wildlife; and
remediation of groundwater will eliminate potential exposure to a future resident via ingestion or
inhalation, and will help to restore the aquifer.
At the Garage and Storage Area; Excavation of soils will eliminate exposure via direct contact
to a future resident and exposure to terrestrial wildlife.
At the Downgradient Groundwater Area: Remediation of groundwater will help to restore the
aquifer; and institutional controls will prevent use of contaminated groundwater prior to
achievement of cleanup levels.
The selected remedy will reduce potential human health risk levels such that they do not exceed
EPA's acceptable risk range of 10"4 to 10"6 for incremental carcinogenic risk and such that the
non-carcinogenic hazard is below a level of concern. It will reduce potential human health risk
levels to protective ARARs levels, Le^, the remedy will comply with ARARs and To Be
Considered criteria. The remedy provides adequate protection of the environment by addressing
risks to terrestrial wildlife in upland soils (FDDA and GSA) and by addressing risks to aquatic
life in surface water and sediments (Sutton Brook between the landfill lobes). Implementation of
the selected remedy will not pose any unacceptable short-term risks or cause any cross-media
impacts.
At the time that the ARAR based Ground Water Cleanup Levels identified in the ROD and
newly promulgated ARARs and modified ARARs that call into question the protectiveness of
the remedy have been achieved and have not been exceeded for a period of three consecutive
years, a risk assessment shall be performed on the residual ground water contamination to
determine whether the remedy is protective. This risk assessment of the residual ground water
contamination shall follow EPA procedures and will assess the cumulative carcinogenic and non-
carcinogenic risks posed by ingestion of ground water and inhalation of VOCs from domestic
water usage. If, after review of the risk assessment, the remedy is not determined to be
protective by EPA, the remedial action shall continue until protective levels are achieved and
have not been exceeded for a period of three consecutive years, or until the remedy is otherwise
deemed protective. These protective residual levels shall constitute the final cleanup levels for
this Record of Decision and shall be considered performance standards for any remedial action.
2, The Selected Remedy Complies With ARARs
The selected remedy will comply with all Federal and any more stringent State ARARs that
pertain to the Site. See the tables in Appendix D for a list of all ARARs and To Be Considered
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requirements for the selected remedy. In addition, since wastes (i.e., contaminated soils from the
FDDA and GSA and sediments from Sutton Brook between the Landfill Lobes) will be moved
within the same "area of contamination" (AOC) to be consolidated with the Landfill Lobes prior
to the construction of the landfill cap, Land Disposal Restrictions (LDRs) do not apply,
3. The Selected Remedy is Cost-Effective
In the EPA's judgment, the selected remedy is cost-effective because the remedy's costs are
proportional to its overall effectiveness (see 40 CFR 3Q0.430(f)(l)(ii)(D)). This determination
was made by evaluating the overall effectiveness of those alternatives that satisfied the threshold
criteria (i.e., that are protective of human health and the environment and comply with all
Federal and any more stringent State ARARs, or as appropriate, waive ARARs), Overall
effectiveness was evaluated by assessing three of the five balancing criteria ~ long-term
effectiveness and permanence; reduction in toxicity, mobility, and volume through treatment;
and short-term effectiveness, in combination. The overall effectiveness of each alternative then
was compared to the alternative's costs to determine cost-effectiveness. The relationship of the
overall effectiveness of this remedial alternative was determined to be proportional to its costs
and hence represents a reasonable value for the money to be spent.
For the Landfill Lobes, EPA has determined that the selected remedy, alternative LF-2b, is cost-
effective as it meets both threshold criteria and is reasonable given the relationship between the
overall effectiveness afforded by the other alternatives and cost compared to the other
alternatives. The available alternatives are closely comparable with regard to both the long-term
effectiveness and permanence criterion and the short-term effectiveness criterion. With regard to
the reduction of toxicity, mobility and volume through treatment, alternative LF-2a, does not
satisfy this criterion unless the contingency for groundwater treatment is triggered. Alternatives
LF-3 and LF-4 both contain groundwater treatment as a component and satisfy this criterion, but
at significant incremental cost ($6.2 million and $15.7 million respectively) above the cost of
LF-2b (which also satisfies the reduction of toxicity, mobility and volume through treatment
criteria), without providing commensurate incremental benefit. Although modeling does not
clearly show a shorter cleanup timeframe associated with LF-2b over LF-2a, the installation of
the vertical barrier will serve to concentrate the discharge of all of the contaminated groundwater
from the Southern Lobe at its western edge (where only a limited amount of groundwater
currently discharges). The vertical barrier also prevents the contaminated groundwater plume
from discharging directly to Sutton Brook. The concentration of contaminated groundwater at
the western edge of the Southern Lobe, justifies active groundwater treatment at that location.
For the Former Drum Disposal Area, EPA has determined that the selected remedy, alternative
FDDA-4, is cost effective as it meets both threshold criteria and is reasonable given the
relationship between the overall effectiveness afforded by the other alternatives and cost
compared to the other alternatives. The available alternatives are closely comparable for the
most part with regard to both the long-term effectiveness and permanence criterion and the short-
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term effectiveness criterion, with FDDA-2 having slightly less long-term effectiveness as capped
contaminated soils may have the potential to leach to groundwater. With regard to the reduction
of toxicity, mobility and volume through treatment, alternatives FDDA-2, FDDA-3 and FDDA-5
satisfy this criterion, while alternative FDDA-4 does not satisfy this criterion unless the
contingency for groundwater treatment is triggered. However, the incremental cost associated
with achieving this criteria and the relative incremental benefit is not justifiable. At an estimated
increased cost of $4.7 or $4,8 million, it is estimated that groundwater associated with the FDDA
will at best achieve cleanup goals 6-12 years faster than under FDDA-4 (24-30 years estimated,
versus 36 years estimated). In addition, the Former Drum Disposal Area is upgradient of the
Downgradient Groundwater Area. The shortest estimate for attaining groundwater cleanup
levels at the Downgradient Groundwater Area, is 57 years. Therefore, the added cost of $4.7-
$4.8 million is not warranted, and FDDA-4 is determined to be cost effective.
For the Garage and Storage Area, EPA has determined that the selected remedy, alternative
GSA-2, is cost effective as it satisfies both threshold criteria and is reasonable given its overall
cost and effectiveness. It is the only GSA alternative which satisfies both threshold criteria.
For the Downgradient Groundwater Area, EPA has determined that the selected remedy,
alternative DGGW-2, is cost effective as it satisfies both threshold criteria and is reasonable
given the relationship between the overall effectiveness afforded by the other alternatives and
cost compared to the other alternatives. The available alternatives are closely comparable for the
most part with regard to both the long-term effectiveness and permanence criterion and the short-
term effectiveness criterion, with DGGW-2 having greater short-term effectiveness due to less
wetlands impacts from installation of components of the treatment system. With regard to the
reduction of toxicity, mobility and volume through treatment, alternatives DGGW-3 and DGW-4
satisfy this criterion, while alternative DGGW-2 does not satisfy this criterion unless the
contingency for groundwater treatment is triggered. However, the incremental cost to satisfy this
criterion is $8 million. The benefit received for the $8 million increased cost, is that it is
estimated that groundwater cleanup levels will be achieved in as few as 57 years, rather than as
few as 67 years (the alternative DGGW-2 estimate). The incremental benefit realized by the
added cost is not balanced by a comparable incremental benefit in overall effectiveness.
Alternative DGGW-2 is considered to be cost effective as it provides the best balance of cost and
overall effectiveness.
4. The Selected Remedy Utilizes Permanent Solutions and Alternative Treatment or
Resource Recovery Technologies to the Maximum Extent Practicable
Once the Agency identified those alternatives that attain or, as appropriate, waive ARARs and
that are protective of human health and the environment, EPA identified which alternative
utilizes permanent solutions and alternative treatment technologies or resource recovery
technologies to the maximum extent practicable. This determination was made by deciding
which one of the identified alternatives provides the best balance of trade-offs among
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alternatives in terms of: 1) long-term effectiveness and permanence; 2) reduction of toxicity,
mobility or volume through treatment; 3) short-term effectiveness; 4) implementability; and 5)
cost. The balancing test emphasized lone-term effectiveness and permanence and the reduction
of toxicity, mobility and volume through treatment; and considered the preference for treatment
as a principal element, the bias against off-site land disposal of untreated waste, and community
and State acceptance. The selected remedy provides the best balance of trade-offs among the
alternatives.
For the Landfill Lobes, the selected remedy and the other available alternatives are closely
comparable with regard to the long-term effectiveness and permanence criterion, and the short-
term effectiveness criterion. The selected remedy includes reduction of toxicity, mobility and
volume through treatment of groundwater at the Southern Lobe, providing additional benefit
without additional, unwarranted cost.
For the Former Drum Disposal Area, the selected remedy and the other available alternatives are
closely comparable for the most part with regard to both long-term effectiveness and
permanence, and short-term effectiveness, with FDDA-2 having slightly less long-term
effectiveness. The selected remedy will utilize treatment of groundwater if treatment actions are
triggered. All available alternatives are similar with regard to implementability. The selected
remedy provides the best balance of the tradeoffs among the alternatives
For the Garage and Storage Area, the selected remedy is the only alternative that is protective of
human health and the environment, attains ARARs, and achieves remedial objectives quickly
and cost effectively.
For the Downgradient Groundwater Area, the selected remedy and the other available
alternatives are closely comparable for the most part with regard to both long-term effectiveness
and permanence, and short-term effectiveness, with DGGW-2 having greater short-term
effectiveness due to less wetlands impacts from installation of components of the treatment
system. The selected remedy will utilize treatment of groundwater if treatment actions are
triggered. All available alternatives are readily implementable. With regard to cost, very little
benefit is gained by significant incremental increases in cost. The selected remedy provides the
best balance of the tradeoffs among the alternatives.
5, The Selected Remedy Satisfies the Preference for Treatment Which Permanently
and Significantly Reduces the Toxicity, Mobility or Volume of the Hazardous
Substances as a Principal Element
The principal elements of the selected remedy are:
-Excavation of contaminated soils exceeding site-specific cleanup levels from the Former
Drum Disposal Area (FDD A) and the former Garage and Storage Area (GS A);
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-Excavation of contaminated soils and sediments exceeding site-specific cleanup levels from
a portion of Sutton Brook between the two landfill lobes;
-Consolidation of excavated soils and sediments along with other debris adjacent to the
landfills into the landfills;
-Construction of a low permeability cap over both landfill lobes, including systems to collect
and manage gases and storm water from the landfills;
-Construction of a vertical barrier to intercept groundwater from the southern landfill lobe to
prevent it from entering Sutton Brook;
-Collection and treatment of contaminated groundwater from an area west of the southern
landfill lobe;
-Monitored natural attenuation of areas of groundwater contamination not captured by the
extraction system, with a contingency to expand the area of active groundwater
remediation, if necessary;
-Institutional controls such as deed restrictions and/or local ordinances to prevent
unacceptable exposures to wastes left in place and to restrict exposure to
contaminated groundwater until cleanup levels are met;
-Long-term groundwater, surface water, and sediment monitoring, and periodic five-year
reviews of the remedy.
The selected remedy satisfies the statutory preference for treatment as a principal element by
treating contaminated groundwater. As described earlier, if triggered the scope of groundwater
treatment will be expanded.
6. Five-Year Reviews of the Selected Remedy are Required
Because this remedy will result in hazardous substances remaining on-site above levels that
allow for unlimited use and unrestricted exposure, a review will be conducted within five years
after initiation of the remedial action to ensure that the remedy continues to provide adequate
protection of human health and the environment.
N. DOCUMENTATION OF NO SIGNIFICANT CHANGES
EPA presented a proposed plan for remediation of the Site on June 27,2007.
The major components of the preferred alternative include the following:
Excavation of contaminated soils exceeding site-specific cleanup levels from the
Former Drum Disposal Area (FDDA) and the former Garage and Storage Area
(GSA);
Excavation of contaminated soils and sediments exceeding site-specific cleanup
levels from a portion of Sutton Brook between the two landfill lobes;
Consolidation of excavated soils and sediments along with other debris adjacent to
the landfills into the landfills;
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Construction of a low permeability cap over both landfill lobes, including systems to
collect and manage gases and storm water from the landfills;
Construction of a vertical barrier to intercept groundwater from the southern landfill
lobe to prevent it from entering Sutton Brook;
Collection and treatment of contaminated groundwater from an area west of the
southern landfill lobe;
Monitored natural attenuation of areas of groundwater contamination not captured by
the extraction system, with a contingency to expand the area of active groundwater
remediation, if necessary;
Institutional controls such as deed restrictions and/or local ordinances to prevent
unacceptable exposures to wastes left in place and to restrict exposure to
contaminated groundwater until cleanup levels are met;
Long-term groundwater, surface water, and sediment monitoring, and periodic five-
year reviews of the remedy.
EPA reviewed all written and verbal comments submitted during the public comment period.
It was determined that no significant changes to the remedy, as originally identified in the
proposed plan, were necessary.
O. STATE ROLE
The Massachusetts Department of Environmental Protection (MassDEP), as representative
for the Commonwealth of Massachusetts, has reviewed the various alternatives and has indicated
its support for the selected remedy. The MassDEP has also reviewed the Remedial Investigation,
Risk Assessment and Feasibility Study to determine if the selected remedy is in compliance with
applicable or relevant and appropriate State environmental and facility siting laws and
regulations. MassDEP, as representative for the Commonwealth of Massachusetts, concurs with
the selected remedy for the Sutton Brook Disposal Area Site. A copy of the declaration of
concurrence is attached as Appendix A.
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PART 3: THE RESPONSIVENESS SUMMARY
There has been extensive community participation during the Remedial Investigation/Feasibility
Study process for the Sutton Brook Disposal Area Superfund Site. A more detailed summary of
community coordination and involvement is outlined in Section C of Part 2 of the ROD,
Community Participation.
EPA published a notice of availability of the Proposed Plan and Administrative Record in the
Lowell Sun on June 15, 2007 and released its Proposed Plan to the public on June 27, 2007.
EPA also held a public information session on June 27,2007 at the Tewksburv Town Library in
Tewksbury, Massachusetts, and a Public Hearing on July 18, 2007, also at the Town Library.
Transcripts were created for both meetings and have been made part of the Administrative
Record for this Record of Decision. In addition to the oral comments, a number of written
comments were provided on the Proposed Plan. The full text of all written and oral comments
received during the comment period has been included in the Administrative Record.
Outlined below is a summary of significant comments received from the public and other
interested parties during the public comment period and EPA's response to
those comments. Similar comments have been summarized and grouped together, and
technical and legal issues have been divided into a number of general categories. These general
categories are summarized as follows:
A. Questions and Comments Regarding Consolidation of Soils from Other Areas and
Capping of the Landfill Lobes
B. Questions and Comments Regarding the Approach to Groundwater Cleanup
C. Questions and Comments Regarding the Scope of the Remedial Investigation and
Feasibility Study (RI/FS)
D. Questions and Comments Regarding Liability, Enforcement, and the Timetable for
Remedy Implementation
A. Questions and Comments Regarding Consolidation of Soils from Other Areas and
Capping of the Landfill Lobes:
A. 1. Several commenters expressed concern about the volume of capping materials that would
be required to be brought to the Site under the Preferred Alternative, citing concerns
about public safety, road deterioration, noise, dust, and air emissions. Many of these
same commenters asked EPA to explore trucking routes that minimized disturbance to
the residential community near the Site.
EPA Response:
EPA acknowledges that a significant volume of material will need to be transported to the
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Site in order to construct the remedy. At present, South Street is the only route available
for trucks to access the Site. As planning for the remedy progresses, and at the time that
the remedy is implemented, EPA will work with the local community (including the
police department, fire department, and school department), the construction contractor(s)
that will be transporting materials, and the Potentially Responsible Parties (PRPs), to
agree on a route or routes to access the Site, as well as to address other transportation
issues (such as time of operations and locations of special concern) that may be
identified.
A.2 Several questions were raised regarding the appropriate design for the landfill caps and
the regulatory requirements should be considered Applicable or Relevant and
Appropriate Requirements (ARARs) that would govern such design (i.e., RCRA Subtitle
C hazardous waste regulations or state solid waste regulations).
EPA Response:
EPA has determined that RCRA Subtitle C hazardous waste regulations are applicable at
the Site, and, as ARARs, they govern the landfill's closure/capping requirements.
Because RCRA-type (listed or characteristic) hazardous wastes were disposed of at the
Site during the operation of the landfill, which included disposal after 1980, the cap
design and construction shall meet RCRA Subtitle C hazardous waste standards.
Notwithstanding the applicability of these RCRA Subtitle C ARARs, there is flexibility
in the design of the cover to meet the Subtitle C performance standards. The details of
cap materials and construction will be Finalized during remedial design.
The comment letter from the PRP group also contained data comparing groundwater
contaminant levels at the Northern Lobe with groundwater monitoring data from a set of
solid waste landfills. The comment argues that the data are comparable and justify
selecting a solid waste cap for the Northern Lobe. As described above, EPA made its
determination based on the evidence of hazardous waste disposal at the Site. The
comparison of groundwater monitoring data is not germane in determining the
applicability of the RCRA Subtitle C hazardous waste regulations.
A.3 One commenter noted that EPA should require that materials consolidated from other
areas into the landfill lobes be placed above the water table to avoid contact with
groundwater and to ensure that these materials do not serve as an ongoing source of
groundwater contamination.
EPA Response:
EPA agrees with the comment. Consolidated material will be placed above the water
table.
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A.4 One commenter requested that the landfill be designed so that future use is possible.
EPA Response:
Reuse of previously contaminated properties is a goal of EPA. At this Site, the volume of
waste material contained in the landfill lobes, the limited extent of upland area on Site,
the proximity of wetlands to the lobes and the access road along the northern lobe, all
serve to place limitations on reuse possibilities (See Figure E-2). The wetlands and the
access road, essentially eliminate the possibility of flattening out the Northern Lobe
which would be necessary for something like athletic fields, and would also require
expanding the footprint of the Northern Lobe. In addition, regulations exist requiring that
impacts to wetlands and wetland loss be avoided to the extent practicable. There is a
possibility of incorporating future use into the landfill lobe design, although any use
would need to be compatible with preserving the protectiveness of the remedy and would
need to be incorporated into the remedial design process.
A.5 Citing implementability and flooding concerns, one commenter expressed strong
opposition to alternative LF-4, which evaluated re-routing of Sutton Brook around the
landfill lobes.
EPA Response:
EPA agrees that alternative LF-4 is not the best choice for addressing risks associated
with the landfill lobes. As documented in the Feasibility Study as well as earlier in this
Record of Decision, when comparing the various alternatives against the required "nine-
criteria," alternative LF-4 is not, on balance, the strongest alternative. The most
significant issues which weigh against alternative LF-4 are the extensive wetland impacts
that would result in order to implement the alternative. As a result, EPA has determined
that LF-4 fails to meet location specific ARARs.
B. Questions and Comments Regarding the Approach to Groundwater Cleanup:
>wmi— I i i. . w..i — ii . i li.»
B. 1. The Massachusetts Department of Environmental Protection (MassDEP) as well as the
community group, TOXIC, Inc. commented in support of EPA's proposal for
groundwater treatment in the area of the landfill's Southern Lobe. Another commenter
asked for more information on the rationale for groundwater treatment at the Southern
Lobe but not the Northern Lobe.
EPA Response:
As stated elsewhere, EPA has determined that active groundwater treatment at the
western edge of the Southern Lobe is warranted due to the high level of groundwater
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contamination at the Southern Lobe. Active groundwater treatment is further warranted
due to the concentrating and focusing of contaminated groundwater at the western edge
of the Southern Lobe, which will occur when the vertical barrier is installed as part of the
remedy. The vertical barrier will prevent the migration of highly contaminated
groundwater to Sutton Brook, and will direct contaminated groundwater at the Southern
Lobe in a westerly direction to the "Area for Focused Groundwater Treatment" (see
Figure L-l), where active groundwater treatment will occur. The driving factor in EPA
not requiring active groundwater treatment at the Northern Lobe is that, while
groundwater from the Northern Lobe is contaminated, it is contaminated at significantly
lower concentrations when compared to groundwater at the Southern Lobe (a high
concentration of 842 parts per billion of total VOCs at the Northern Lobe, and a high
concentration of 57,210 parts per billion of total VOCs at the Southern Lobe). EPA has
determined that the natural attenuation which is presently occurring, coupled with the
capping of the Northern Lobe, will adequately address the groundwater contamination
associated with the Northern Lobe. It should be noted, that in general, groundwater from
the Northern Lobe flows through the FDDA and the DGGW areas. Because of this, if the
groundwater contingency were to be implemented at either the FDDA or the DGGW,
groundwater which had originated at the Northern Lobe would be addressed (whether it
needed to be, or not).
B.2 One commenter requested clarification of the duration of the planned groundwater
remediation at the Southern Lobe and whether EPA planned to establish criteria for
shutting down such treatment in the future.
EPA Response:
As described in this Record of Decision, active groundwater treatment will be initiated
after implementation of the source control portions of the remedy (capping and vertical
barrier) at the Southern Lobe. The reason for starting groundwater treatment after the cap
and vertical barrier have been constructed is that it is expected that groundwater
dynamics (flow direction, flow rates, groundwater elevation, etc.) will be affected by
these source control measures. The active groundwater treatment will be most effective
if it can account for the then-current groundwater conditions.
As described in the Record of Decision, groundwater treatment will continue until
cleanup levels have been met at the edge of the Southern Lobe. After cleanup levels have
been met, which is estimated to occur in 65 years to 210 years, the groundwater at the
edge of the Southern Lobe will continue to be monitored for three additional years to
ensure that the cleanup levels continue to be met and the remedy is protective. Since
wastes will be left in place as part of the selected remedy, the NCP requires periodic
reviews of the remedy. A comprehensive review will be conducted at least every five
years to evaluate the protectiveness of the remedy.
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B.3. Comments on behalf of the PRPs who performed the RI/FS were provided arguing for
delayed implementation of any active groundwater treatment and supporting monitored
natural attenuation (MNA) as the remedy for the Southern Lobe area.
EPA Response:
EPA has determined that it is appropriate to implement active groundwater treatment at
the Southern Lobe following completion of the construction of the landfill cap and the
vertical barrier. EPA does not agree that a delay is warranted. Currently, high
concentrations of contaminants in groundwater exist at the "Area for Focused
Groundwater Treatment" along the western edge of the Southern Lobe (See Figure L-l).
Following construction of the vertical barrier, virtually all contaminated groundwater
associated with the Southern Lobe will migrate through the "Area for Focused
Groundwater Treatment," rather than the majority of it discharging directly to Sutton
Brook as currently occurs. This is necessary to prevent contaminated groundwater from
continuing to contaminate surface water and sediment within Sutton Brook. This will
significantly add to the overall contaminant load at the "Area for Focused Groundwater
Treatment", Because of these issues (current high contaminant levels and expected
additional contaminant load), EPA has determined that MNA will not be adequate in this
area and that it is appropriate to start active groundwater treatment following
implementation of the source control measures (cap and vertical barrier) at the Southern
Lobe. As described in Section L., the selected remedy calls for pre-design studies to
identify the precise combination of remedial processes necessary to treat groundwater.
B.4. Comments on behalf of the community group, TOXIC, Inc., questioned the
appropriateness of selecting MNA as a component of the groundwater remedy.
EPA Response:
EPA has determined that the Remedial Investigation supports the conclusion that MNA is
currently occurring within groundwater at the Site. MNA, along with the mostly
horizontal flow of groundwater, the general absence of contaminant migration to bedrock
and overall slow groundwater movement, are helping to limit the spread of the
contaminated groundwater plume. EPA has determined that the source control measures
to be implemented as part of the remedy (including the excavation of contaminated soils
and sediments and the installation of the landfill cover) will eliminate or reduce ongoing
sources of contamination and will serve to support the success of MNA. However, as
stated in this ROD, if MNA is determined to be not effective, the remedy contains a
contingency whereby active groundwater treatment will be implemented.
B.5. A number of commenters requested that the ROD explain the process and triggers for
moving to active remediation for areas where MNA is selected as a remedy with a
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contingency for future treatment. Many of these comments also expressed concern about
the timing of the first such evaluation (which EPA proposed to be conducted during the
first Five-Year Review).
EPA Response:
Section L of this Record of Decision discusses the remedy, including the triggers for
potentially changing from MNA to active groundwater remediation. Briefly,
groundwater will be monitored for indicators to demonstrate that conditions remain that
are conducive to MNA, as well as to demonstrate that MNA is, in fact, occurring, and
that MNA is effective in addressing groundwater contamination at the Site.
The following criteria are among those which will be considered to determine whether
MNA continues to be the appropriate remedy to address groundwater contamination:
• Contaminant concentrations in groundwater at specified locations exhibit an
increasing trend not originally predicted during remedy selection;
• Near-source wells exhibit large concentration increases indicative of a new or
renewed release;
• Contaminants are identified in monitoring wells located outside of the original plume
boundary;
• Contaminant concentrations are not decreasing at a sufficiently rapid rate to meet the
remediation objectives; and
• Changes in land and/or groundwater use will adversely affect the protectivencss of
the MNA remedy.
If EPA determines that MNA will not meet Remedial Action Objectives, active
groundwater treatment will be required. The Remedial Design/Remedial Action Scope of
Work (RD/RA SOW), which will govern the implementation of the design and
construction of the remedy, will detail the timing and technical and design steps required
in order to implement active groundwater treatment.
Part 2 of the Record of Decision states that "EPA will evaluate the progress of the MNA
portion of the remedy toward achieving RAOs as data become available, but no less
frequently than during the 5-Year Reviews conducted for the Site." EPA is required to
conduct 5-Year Reviews at the Sutton Brook Disposal Area Site, at a minimum, every 5
years after the commencement of the Remedial Action, which is defined as when the
Remedial Design is completed. As the source control activities are expected to take 2-3
years to implement, EPA expects that at most there will be 2-3 years of monitoring data
at the time of the first 5-Year Review. Given that the source control activities arc
expected to impact groundwater elevation, flow direction and rate, as well as contaminant
load, EPA has determined that an estimated 2-3 year period between the completion of
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the source control activities (capping and soil excavation) and the initiation of the first 5-
Year Review evaluation is not excessive.
B.6, Comments on behalf of the community group, TOXIC, Inc., requested clarification on the
type of vertical barrier proposed for the Southern Lobe, stressing opposition to a "hanging
barrier," which might allow groundwater to flow under the barrier.
EPA Response:
In order to prevent migration of contaminated groundwater under the vertical barrier, the
base of the barrier will be "tied-in" to an impermeable or low-permeability layer (e.g., till
or bedrock). This requirement is noted in Section L in Part 2 of this ROD.
B.7. Comments on behalf of the community group, TOXIC, Inc., expressed support for
alternatives FDDA-3 and DGGW-3, rather than EPA's preferred alternatives for those
areas.
EPA Response:
Alternatives FDDA-3 and DGGW-3 each has active groundwater treatment as a
component. EPA has determined that the source control actions that will be taken at the
Site (including landfill cover, vertical barrier, and source removal) will be effective and
will, in combination with MNA, meet site objectives. EPA has determined that the added
estimated expense of FDDA-3 (approximately $4.8 million) and DGGW-3
(approximately $7 million) is not justified given that the gains predicted for the amount
of time to achieve cleanup levels under FDDA-3 and DGGW-3 are modest. As stated
and described earlier, if EPA determines that MNA is not effective in addressing
groundwater contamination, the remedy has a contingency whereby active groundwater
treatment would be implemented at the Former Drum Disposal Area, the Downgradient
Groundwater Area, or both areas,
B.8. Comments on behalf of the Massachusetts Bay Transportation Authority (MBTA)
suggested that the groundwater at the Site be re-classified as a non-potential drinking
water supply and that the remedy should not be based on restoration to drinking water
standards.
EPA Response:
Consistent with EPA's 1995 Final Ground Water Use and Value Determination
Guidance, the MassDEP completed a "Groundwater Use and Value Determination" in
July 2001, for groundwater at and in the vicinity of the Sutton Brook Disposal Area Site.
The purpose of the Use and Value Determination is to identify whether the aquifer at the
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Site should be considered of "High," "Medium," or "Low" use and value. In the
development of this Determination, MassDEP applied the criteria for groundwater
classification as promulgated in the Massachusetts Contingency Plan (MCP). The
classification contained in the MCP considers criteria similar to those recommended in
the EPA Use and Value Guidance. MassDEP's recommendation supports a Medium Use
and Value for the groundwater underlying the Site. Evaluation criteria utilized in the Use
and Value Determination for the Sutton Brook Disposal Area support the classification of
the aquifer as a potential drinking water supply. As such, potential use of the aquifer as a
drinking water supply must be considered by EPA in setting cleanup levels and in
choosing a remedy.
The Groundwater Use and Value Determination can be found in Appendix B.
B.9. One commenter requested further details on the rationale for MNA in some areas and
collection and treatment in other areas, as well as an explanation of where long-term
monitoring would be conducted.
EPA Response:
EPA has determined that active groundwater treatment at the western edge of the
Southern Lobe is warranted due to the high level of groundwater contamination at the
Southern Lobe. Active groundwater treatment is further warranted due to the
concentrating and focusing of contaminated groundwater at the western edge of the
Southern Lobe, which will occur when the vertical barrier is installed as part of the
remedy. The vertical barrier will prevent contaminated groundwater from discharging
directly to Sutton Brook and re-contaminating surface water and sediments, and will help
direct contaminated groundwater at the Southern Lobe in a westerly direction to the
"Area for Focused Groundwater Treatment" (see Figure L-l), where active groundwater
treatment will occur. EPA is concerned that without active groundwater treatment, the
focusing of additional contaminated groundwater to an area that is already experiencing
high levels of groundwater contamination would be too much for MNA alone to address.
EPA has determined that MNA is currently occurring within groundwater at the Site and
is helping (along with groundwater flow patterns) to restrict the spread of the
contaminated groundwater plume. EPA has determined that the source control measures
to be implemented as part of the remedy (including excavating contaminated soils and
sediments and capping landfill lobes), will eliminate or reduce ongoing sources of
contamination and will serve to support the success of MNA in the areas where active
groundwater treatment is not proposed.
The actual locations for long-term groundwater monitoring, will be determined during
remedial design (and may be subsequently modified if groundwater conditions change).
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At this Site, there are three purposes for the monitoring. One purpose, as has been
discussed, is to monitor the progress of MNA, and assess whether MNA is adequate to
address groundwater contamination. A second purpose is to monitor whether and when,
groundwater cleanup levels have been achieved. Cleanup levels must be achieved at and
beyond the "point of compliance." For the Landfill Lobes, the point of compliance is
defined as the edge of the Lobes. Long-term monitoring wells will be installed
downgradient of the landfill to monitor this point of compliance. The third purpose of
long-term monitoring is to monitor the size and location of the contaminated groundwater
plume to ensure that it is not spreading beyond its current bounds. In order to make this
assessment, wells would need to be located beyond the current bounds of the plume.
C. Questions and Comments Regarding the Scope of the Remedial Investigation and
Feasibility Study (Rl/FS):
C. 1. One commcnter expressed concern that data from residential properties at Bemis Circle
and Homestead Lane were not adequately factored into the remedial investigation or
decision-making. Two commenters asserted that data from the so-called Perkins
Property, northeast of the northern lobe, had not been adequately considered and
improperly considered as a "background" location.
EPA Response:
As stated in the comment, past investigations have occurred at the Bemis Circle property.
These investigations involved the sampling of groundwater, soils, soil gas and indoor air.
In general, detected contaminants were present at very low concentrations, and with
regard to groundwater in particular (the presumed transport mechanism for any
contamination, if one were to exist), the concentrations were well below any potential
action level. EPA does not agree with the commentors' conclusion that data suggest that
the source of contamination is "in the direction of the landfill and the Former Drum
Disposal Area." Groundwater from three wells on the property was sampled and
analyzed in December 2006. Results at all three wells showed very low levels of a few
contaminants, with the well closest to the Sutton Brook Disposal Area showing fewer
contaminant detections than the next closest well. Lines of evidence (local and regional
groundwater flow directions as determined by groundwater elevations in monitoring
wells, contaminant distribution and concentrations in groundwater throughout the area),
support the RI conclusion that Sutton Brook is the dominant water feature in the area, and
that groundwater flows towards Sutton Brook. This evidence shows that groundwater
from the Site source areas flows to Sutton Brook rather than to Bemis Circle.
EPA has determined that groundwater from the Sutton Brook Disposal Area Superfund
Site is not the cause of this contamination and that there is insufficient evidence to
support this conclusion.
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Regarding the Homestead Lane property, EPA has determined that this property is
upgradient of the Sutton Brook Disposal Area. As such, any contamination found on this
property would not have been the result of contamination at the Site, Nonetheless, It was
EPA's intention that the irrigation well on the property be re-sampled during the RI/FS.
Unfortunately, difficulties coordinating with the homeowner prevented re-sampling from
occurring prior to completion of the RI/FS (although the homeowner does not object to
the sampling). Re-sampling of the groundwater at this property will be conducted as part
of future groundwater monitoring.
The Perkins Property is located northeast of the landfill, across the former railroad bed.
EPA acknowledges that groundwater from the Northern Lobe may have impacted the
edge of the Perkins Property due to hydraulic mounding; this is shown on figures in the
RI report. However, although a comment notes that the property "has not previously
been used for any commercial, industrial, or residential use other than possibly
homesteading and grazing by livestock," there is evidence that activities such as
excavation, filling, and disposal, have occurred on the property. As the groundwater flow
direction is generally from the Perkins Property towards the Northern Lobe and Sutton
Brook, the extent of the hydraulic mounding is not anticipated to be significant. The data
evaluated during the RI phase of the project did not show significant detections at the
locations which are currently considered "reference." These findings did not justify
further sampling in that area to refine the extent of contamination in that area.
During the design and remedy implementation phase of the selected remedy, a landfill
monitoring program will be established. At that time, EPA will review any new
information, as well as perform additional testing regarding the extent of the landfill (and
associated contamination) to properly implement the monitoring program,
C.2 One commenter noted that two other sites had not been adequately considered as part of
the site investigation, 79 McDonald Road and the Kroehmal Farm site (also known as
the Wilmington Disposal Area), and asked about the regulatory status of the Kroehmal
Farm property.
EPA Response:
At the time that the documentation proposing the Sutton Brook Disposal Area to the
National Priorities List (NPL) was being compiled, there existed three known areas
which were in the process of undergoing removal actions (79 McDonald Road, the
Kroehmal Farm Site or Wilmington Disposal Area, and Rocco's Landfill). When the Site
was proposed to the NPL, there was no certainty as to whether the removal actions would
be completed prior to final site listing or if additional work (removal or investigations)
would be necessary. The language proposing the Site to the NPL was intended to be
flexible to allow for inclusion, as part of the Site, of any removal area at which either the
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removal had not been completed, or at which follow-up activities remained which would
be appropriately addressed under Superfund.
At the time when the Sutton Brook Disposal Area Superfund Site's NPL listing was
finalized in June 2001, the 79 McDonald Road removal had been completed by the
property owners, and applications had been made for the property to be further addressed
as necessary, within the Massachusetts Chapter 21E Cleanup Program. The removal at
the Krochmal Farm/Wilmington Disposal Area had been completed by EPA, EPA and
MassDEP agreed at that time that there was a remaining soil issue to be addressed (low
concentrations of PCBs) and that MassDEP would take the lead in addressing it. It was
further agreed that, given the relatively minor nature of the remaining issue, there was no
reason to include that area in the final listing of the Site, It should be noted that EPA had
already completed extensive electromagnetic (EM) surveys within the farm property
searching for drums and buried waste.
MassDEP has informed EPA that the Krochmal Farm site has a Release Tracking
Number and is within their tracking system.
C.3. The MBTA asked whether the RI/FS documented impacts to benthic organisms and
whether EPA had evaluated the long-term benefits of re-establishing benthic organisms
vs. short-term impacts of the proposed Sutton Brook sediment excavation.
EPA Response:
The site channel portion of Sutton Brook directly between the landfill lobes was
evaluated by a comparison of five surface water and sediment samples to effects-based
NOAEL (No Observed Adverse Effects Level) benchmarks in the screening-level step of
the Baseline Ecological Risk Assessment (BERA). Consistent with EPA's Guidance on
Presumptive Remedy for CERCLA Municipal Landfill Sites, additional baseline
ecological effects assessment of exposure to contaminants in the site channel portion of
the Brook (located between the landfill lobes) was not conducted in the BERA because of
the assumption that a remedy would have to address the high risk of COPCs in the site
channel. In addition, it was assumed that because of the close proximity of Sutton Brook
to the landfill lobes, construction activities would significantly impact this portion of
Sutton Brook and would essentially be equal to excavation of brook sediment. Given that
the contaminant concentrations detected in surface water and sediments in the area
between the landfill lobes exceeded screening-level benchmarks, the PRP group (who
performed the RI/FS) and EPA agreed that making the assumption that surface water and
sediments between the lobes exceeded risk criteria was reasonable. Because of this,
toxicity testing, which would have documented impacts to organisms (if the impacts
exist) was not conducted as part of the RI in this portion of Sutton Brook. The comment
also questioned whether a comparison had been made between the benefits of re-
Sutton Brook Disposal Area Superfund Site, Tewksbury. Massachusetts
Record of Decision
September 2007
Page 108 of 110
-------
Record of Decision
Part 2: The Decision Summary
establishing benthic organisms in Sutton Brook, in between the Landfill Lobes, and the
short-term impacts of excavation and consolidation of sediments. The comparison
suggested was not made, because as described above, significant impacts to the Sutton
Brook sediments in-between the Landfill Lobes are expected due to construction
activities. These expected construction impacts, were the primary reason for only
comparing samples with NOAEL benchmarks, as described above.
C.4. Citing concerns about groundwater mounding and as a means for comparing alternatives,
the MBTA asked whether a site-wide water balance assessment had been completed.
EPA Response:
Water balance assessments (e.g., precipitation, evaporation, groundwater and surface
water flow rates and volumes, infiltration rates, etc.) were conducted during the RI and
the FS in trying to understand water dynamics at the Site and to assess the impact of
different potential remedial components (e.g., capping, vertical barrier, and extraction
wells). Reference to these efforts can be found in Appendix F of the RI, Appendix F of
the FS, as well as in the body of both documents.
C.5. The MBTA requested a detailed review of the cost estimates for each alternative.
EPA Response:
Cost estimates were prepared and developed for the Feasibility Study and the Record of
Decision in accordance with the National Contingency Plan (NCP) and EPA's RI/FS
Guidance. As such, cost estimates are intended to be accurate within +50 to -30 percent
of the actual costs. These costs are intended to be used for comparative purposes, to
allow for cost evaluation between different FS alternatives.
D. Questions and Comments Regarding Liability, Enforcement, and the Timetable for
Remedy Implementation;
D. 1. A number of comments and questions were received regarding identification and
participation of additional Potentially Responsible Parties (PRPs).
EPA Response:
Since July of 2000, when EPA first notified parties of their liability with respect to buried
drums at the Site, EPA has continued to pursue evidence on parties that may have
liability at the Site. The purpose of this pursuit is to find additional potentially liable
parties and ultimately reach a settlement with those parties under which they are
compelled to undertake the cleanup of the Site. At the time of the settlement for
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
Record of Decision
September 2007
Page 109 of 110
-------
Record of Decision
Part 2: The Decision Summary
performance of the RI/FS, EPA had identified 39 parties. Recently EPA notified an
additional 23 parties of their potential liability at the Site. EPA will be meeting with
representatives of these recently notified parties in October 2007. EPA expects to begin
negotiating with all notified parties in the spring of 2008 regarding implementing the
selected remedy.
D.2. A number of questions were raised regarding the timeline for implementation of the
cleanup once the remedy is selected.
EPA Response:
When PRPs are known to exist at a site, EPA is obligated to pursue those parties and
attempt to compel them to conduct site cleanups. This is the case at the Sutton Brook
Disposal Area Site. As mentioned above, EPA will be negotiating with all notified
parties regarding implementing the selected remedy. EPA expects to commence
negotiations with the Site's PRPs by the spring of 2008. The amount of time needed to
reach a settlement is uncertain. Following a settlement or an order, EPA estimates that 1-
1.5 years will be required to design the remedy and that an estimated 2-3 years will be
required to construct the remedy.
D.3. Several commentcrs asked about EPA's planned community notification and involvement
process leading up to and during construction.
EPA Response:
EPA plans to conduct at least one informational meeting during the remedial design
process (probably near completion) in order to discuss aspects of the design and schedule,
as well as any implementation issues. In addition, EPA anticipates at least one, and
probably two, informational meeting(s) during on-site construction to discuss progress
and the upcoming schedule. It is anticipated that these meetings will be supplemented by
informational mailings and/or press releases at key times during the design and
construction process.
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
Record of Decision
September 2007
Page 110 of 110
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Appendix A
MassDEP Letter of Concurrence
-------
Commonwealth of Massachusetts
Executive Office of Energy & Environmental Affairs
Department of Environmental Protection
ONE WINTER STREET, BOSTON, MA 02108 617-292-5500
I AH A. BOWLES
Secretary
LAURIE BURT
Commissioner
September 26,2007
James T. Owens, Director
Office of Site Remediation and Restoration
Region 1
U.S. Environmental Protection Agency
One Congress Street, Suite 1100 (HIO)
Boston, MA 02114-2023
Dear Mr. Owens:
The Department of Environmental Protection (MassDEP) has reviewed the Record of Decision
(ROD) and the Selected Remedial Action Alternative (Selected Remedy) recommended by the U.S.
Environmental Protection Agency (EPA) for the Sutton Brook Disposal Area Superfund Site (the
Site). MassDEP concurs with the Selected Remedy, subject to the matter noted below.
The Site, which is situated on the eastern boundary of the Town of Tewksbury and partially
extends into the Town of Wilmington, is largely undeveloped. Nearby uses include open space,
agriculture and residential. The Selected Remedy addresses several source areas within the Site
by means of containment and treatment of groundwater, excavation of contaminated soil and
sediment and consolidation with landfill waste, and landfill capping. These measures, in
combination with land use restrictions, are intended to address Site risks by preventing exposure
of the public to contaminants above cleanup goals, protecting the constructed remedy, preventing
inappropriate land use, and protecting terrestrial and aquatic wildlife. The major components of
the Selected Remedy include:
• excavation of contaminated soil and sediment above site-specific cleanup levels (soil
at the Garage and Storage Area and the Former Drum Disposal Area, and sediment
from Sutton Brook between the landfill lobes);
• consolidation of excavated soils, sediment, and debris into the landfill;
• construction of a multi-layer impermeable cap over the landfill lobes;
• interception of groundwater from the southern lobe;
• a combination of collection and treatment and monitored natural attenuation for
contaminated groundwater;
• institutional controls; and
This information is available ill alternate format Call Donald M. Gomes, ADA Coordinator at 6I7-S56-I057, TDD Service - 1-800-298-2207.
MassDEP on the World Wide Web: http://www.mass.gov/dep
© Printed on Recycled Paper
DEVAL L. PATRICK
Governor
TIMOTHY P. MURRAY
Lieutenant Governor
Re: ROD Concurrence Letter
Sutton Brook Disposal Area
Superfund Site, Tewksbury, MA
-------
Sutton Brook Concurrence Letter
September 18, 2007
Page 2 of2
• long-term monitoring.
The Selected Remedy calls for institutional controls in certain specified areas in order to prevent
future exposure, but does not provide the details of those institutional controls. Although
MassDEP's ability to evaluate this aspect of the selected remedy is consequently limited, we
acknowledge that the ROD indicates that the details of the institutional controls will be worked
out during the pre-design and remedial design phases. As part of this process, MassDEP
encourages the analysis of institutional controls alternatives and the evaluation of specific types
of institutional controls, in accordance with relevant guidance and policies,1 during the pre-
design and remedial design phases.
MassDEP fully reserves all rights to evaluate and comment upon specific institutional controls
that EPA may propose, and to determine MassDEP's participation, if any, in the development,
implementation, administration and enforcement of such institutional controls as EPA may select
or approve for the Selected Remedy.
MassDEP looks forward to working with you in implementing the Selected Remedy.
If you have any questions or comments, please contact Janet Waldron, Project Manager, at (617)
556-1156
E-file: 5.01 Correspondence/07_0905_MassDEP ConcurrcnceLettcr
1 Reference is made to EPA's final fact sheet titled "Institutional Controls; A Site Manager's Guide to Identifying,
Evaluating and Selecting Institutional Controls at Superfund and RCRA Corrective Action Cleanups" EPA 540-F-
00-005, OSWER 9355.Q-74FS-P dated September 2000."
-------
Appendix B
Groundwater Use and Value Determination
-------
GROUNDWATER USE AND VALUE DETERMINATION
Sutton Brook Disposal Area NPL Site
July 2001
Consistent with the Environmental Protection Agency's (EPA) 1996 Final Ground Water
Use and Value Determination Guidance, the Massachusetts Department of Environmental
Protection (MADEP) has completed a "Groundwater Use and Value Determination" for
groundwater in the vicinity of the Sutton Brook Disposal Area Site (the "Site"), The
purpose of the Use and Value Determination is to identify whether the aquifer at the site
should be considered of "High", "Medium", or "Low" use and value. In the development
of this Determination, the MADEP has applied the criteria for groundwater classification
as promulgated in the Massachusetts Contingency Plan (MCP). The classification
contained in the MCP considers criteria similar to those recommended in the Use and
Value Guidance. The Department's recommendation supports a Medium Use and Value
for the groundwater underlying the site, provided that no new residential supply wells are
identified by the Town of Tewksbury (in the vicinity of the site) and provided that
existing private wells are routinely tested, An explanation for this recommendation is
outlined below.
The Sutton Brook Disposal Area consists of approximately 100 acres of which
approximately 50 acres were used as an unlined/uncapped landfill for the disposal of
municipal, commercial, and industrial wastes, including (but not limited to): solvents,
sewage, refuse, paint sludge, and steel drum reconditioning waste. Waste materials were
deposited between 1957 until 1979 at which time the landfill was ordered closed by the
Tewksbury Board of Health. According to available file information, indiscriminate
dumping is believed to have continued for some time until approximately 1988.
Since approximately 1988, the property has been the focus of numerous environmental
assessments by MA DEP and EPA. These assessments have (in general) included the
installation of monitoring wells and the collection of sediment, soil, groundwater, and
surface water samples. Contaminants frequently detected and thereby associated with the
landfill include (partial listing only): volatile organic compounds (xylene, toluene, and
tricloroethylene); semi volatile organic compounds (phenol, pyrene, fluoranthene, and
chrysene); polyehlorinated biphenyls; and inorganic element (arsenic, chromium, lead,
and mercury). Based on ancillary information, EPA was informed and subsequently
confirmed the presence of several drum disposal areas in the vicinity of the former
landfill. As a result (in 1999 and 2000), EPA Removal personnel mobilized to the site
and excavated and removed approximately 60 drums and associated contaminated soil.
In June 2001, the site was listed on the National Priorities List (NPL). Remedial
activities completed to date have been primarily assessment activities (with the exception
of the time-critical removal as a result of the buried drums). In regards to potential
redevelopment scenarios, only very preliminary discussions have ensued. Based on the
anticipated length of time until this phase of the project, the Department has not
considered any specific redevelopment scenarios in this Groundwater Use and Value
Determination, but assumes that at least a portion of the surrounding area could be
- 1 -
Use and Value for SUTTQNBK.doc
-------
developed. Accordingly, the Department may revise and/or modify this Determination,
as appropriate, based on any final and unforeseen redevelopment scenarios.
For the purposes of this Determination, the groundwater under evaluation is defined as
the groundwater under the boundaries of the Site as shown on the attached map. The
groundwater beneath and in the vicinity of the Site is classified as GW-1 (see description
below) and is designated a Potential Productive Aquifer. Moreover, the aquifer is
categorized by the U.S. Geological Survey (USCS) as "medium yield". The GW-1
designation (and the associated standard) is considered protective of human health as a
result of direct human consumption.
Drinking water for the majority of the Town of Tewksbury (including the area along
South Street in the vicinity of the Site) is supplied by a surface water intake located on
the Merrimac River; however, historically the town obtained its drinking water from nine
public water supply wells. These wells were removed from service between the years of
1972 and 1992 due to VOC and metals contaminations. The closest of these wells is the
Poplar Street Well Field (comprised of Well Nos. 8 through 12) located between 0.2 and
0.5 miles southwest of the site. In 1985, a hydrological evaluation was completed,
including pump tests of two (of the five) Popular Street wells (Well Nos. 8 and 9). The
results of this evaluation concluded that Sutton Brook Disposal Area was most likely not
the source of contaminants to these wells; however, the closest of the wells (Well Nos. 10
through 12) were not part of the pump tests.
According to the Tewksbury Board of Health, there are several private wells within 0.25-
miles of the site (see the attached memo dated February 16, 1999 from Thomas Carbone,
Tewksbury Director of Public Health). The closest known private drinking water well is
the drinking water well serving the on-site residence. This well has been repeatedly
sampled; however, (to date) no contaminants have been detected. The location of this
well is northwest (and presumably cross-gradient) from the Site. Based on recent
conversations with Mr. Carbone (May 2001), a private well survey is being conducted to
better determine the actual number of private wells in the vicinity of the site. Based on
groundwater contour maps developed in 1995, groundwater flow is (locally) towards
Sutton Brook, and regionally towards the west.
For the purposes of completing a risk assessment, considering the GW-1 designation and
the average depth to groundwater in the vicinity (i.e., the perimeter) of the landfill (i.e.,
between 5 to 10 feet below ground surface), the risk assessment factors as it relates to
groundwater beneath the Site should include, but not limited to, the following:
Human Health:
a) Potential human consumption and/or exposure as a result of existing and/or future
private groundwater supply wells;
b) Excavation into groundwater (i.e., worker exposure);
c) Discharge into surface water and the consequential effects of the discharge (i.e.,
wading scenarios, recreation, and fishing); and
d) Potential migration of contaminants to indoor air (within occupied structures) and
subsequent exposure to volatile contaminants (pending development of the site or
on adjacent parcels which might overlie contaminated groundwater).
Use and Value for SUTTONBK.doc
-2-
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Ecological:
a) Effects on the biota that make up the benthic community; and
b) Effects on the biota that feed on or in the benthic community, and on up the food
chain, as determined by the substance's persistence and ability to bioaccumulate.
Table 1 reviews the Site Area with respect to the eight factors contained in the Use and
Value Determination Guidance. In light of the use and value factors and similar criteria
established in the MCP, the Department supports a Medium Use and Value for
groundwater in the vicinity of the Sutton Brook Disposal Site, As stated previously,
pending future development scenarios, modifications to this determination may be
warranted.
Use and Value for SUTTON BK.doc
-3-
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TABLE I
SUTTON BROOK DISPOSAL AREA GROUNDWATER USE AND VALUE DETERMINATION
JULY 2001
Use and Value Factors
Site-specific Considerations
Use and Value Designation
Quantity
The aquifer beneath the site is designated as a medium-yield potentially productive
aquifer by the USGS. Moreover, impacts to groundwater within the review area
have been documented; however, the extent to which groundwater treatment will be
required is unknown.
Medium
Quality
Groundwater beneath the site is contaminated with numerous substances, most
notably: benzene, toluene, phenol, xylene, trichloroethylene, acetone, and various
metals. Moreover, numerous public supply wells were closed as a result of many of
these contaminants (the source of which has not been determined). The closest
interim wellhead protection area is located between 0.5 and 1 mile southeast from
the site (presumably cross-gradient from the on-site source). Contaminants in
groundwater may pose a risk to private well users (in the vicinity of the site) through
ingestion, direct contact, and inhalation of contaminants via volatilization.
Medium
Current Public Drinking Water
Supply
The majority of the residents in the vicinity of the Site are supplied by public
(municipal) water supply; the current source for this water supply is a surface water
intake located on the Mcrrimac River. In general, the residences in the vicinity of the
site have access to this municipal supply; however, there remain several private
wells (including the water supply at the on-site residence) which are operable.
Medium
Current Private Drinking Water
Supply
According to the Town of Tewksbury Board of Health, there are several private well
users in the vicinity of the site. Specific uses of each of the private wells are
unknown (agricultural, domestic, etc.). The closest private water supply (an on-site
bedrock well) has been tested; no contaminants have been identified. This well is
located cross-gradient from on-site sources. Accordingly, these well are threatened
by the potential migration of on-site contaminants.
High
Likelihood and Identification of
Future Drinking Water Use
The site is currently designated as a potentially productive aquifer and several
private wells exist within 0.25 miles of the site. Based on the access to municipal
water in the area, it is not expected that a significant number of new private wells or
any public wells would be installed; however, the potential exists.
Medium
Other Current or Reasonable
Expected Ground Water Use(s)
in Review Area
At this time, there are no other projected uses of groundwater in the Review Area
(excluding of drinking water).
Low
Ecological Value
A portion of the groundwater beneath the site discharges to Sutton Brook and
(therefore) provides hydrologic support for a significant amount of freshwater
wetlands located adjacent to this waterbody.
Medium
-4-
Use and Value for SUTTONBK.doc
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TABLE 1
SUTTON BROOK DISPOSAL AREA GROUNDWATER USE AND VALUE DETERMINATION
JULY 2001 (Concluded)
Public Opinion
Public opinion was solicited during the promulgation of the MCP regulations,
Medium
groundwater standards, and groundwater classifications.
Use and Value for SUTTON BK.doc
-5-
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Appendix D
Tables
-------
Appendix D - Tables - Contents
Table Description
G-l Chemicals of Concern (Soil)
G-2 Chemicals of Concern (Indoor Air)
G-3 Chemicals of Concern (Groundwater - Groups 1 &2)
G-4 Chemicals of Concern (Groundwater - Groups 3-6)
G-5 Cancer Toxicity Data
G-6 Non-Cancer Toxicity Data
G-7 Risk Characterization Summary (GSA)
G-8 Risk Characterization Summary (FDDA - Residential)
G-9 Risk Characterization Summary (Landfill Lobes - Carcinogens)
G-10 Risk Characterization Summary (Landfill Lobes - Non-Carcinogens)
G-l 1 Risk Characterization Summary (Groundwater - Carcinogens) Residential
G-12 Risk Characterization Summary (Groundwater - Non-Carcinogens) Residential
G-13 Risk Characterization Summary (Groundwater - Carcinogens) Worker
G-l4 Risk Characterization Summary (Groundwater - Carcinogens) Worker
G-l 5 Risk Characterization Summary (FDDA - Worker)
G-l 6 Chemicals of Concern (Upper Sutton Brook - Surface Water)
G-l 7 Chemicals of Concern (Upper Sutton Brook - Sediment)
G-l 8 Chemicals of Concern (Aquatic Wetland - Surface Water)
G-l 9 Chemicals of Concern (Aquatic Wetland - Sediment)
G-20 Chemicals of Concern (Wetland Soil)
G-21 Chemicals of Concern (Pond - Surface Water)
G-22 Chemicals of Concern (Pond - Sediment)
G-23 Chemicals of Concern (Upland Soil)
G-24 Ecological - Exposure Pathways of Concern
G-25 Ecological - Protective Chemical of Concern Concentrations
LF-1 Detailed Analysis - LF~ 1
LF-2a Detailed Analysis - LF-2a
LF«2b Detailed Analysis - LF-2b
LF-3 Detailed Analysis - LF-3
LF-4 Detailed Analysis - LF-4
FDDA-1 Detailed Analysis - FDDA-1
FDDA-2 Detailed Analysis - FDDA-2
FDDA-3 Detailed Analysis - FDDA-3
FDDA-4 Detailed Analysis - FDDA-4
FDDA-5 Detailed Analysis - FDDA-5
GSA-1 Detailed Analysis - GSA-1
GSA-2 Detailed Analysis - GSA-2
DGGW-1 Detailed Analysis - DGGW-1
DGGW-2 Detailed Analysis - DGGW-2
DGGW-3 Detailed Analysis - DGGW-3
DGGW-4 Detailed Analysis - DGGW-4
K-l Comparative Analysis - Landfill Lobes
-------
Appendix D - Tables - Contents (continued)
Table Description
K-2 Comparative Analysis - FDDA
K-3 Comparative Analysis - GSA
K-4 Comparative Analysis - DGGW
L-1 Cleanup Levels - Human Health - Groundwater
L-2 Cleanup Levels - Human Health - Soil
L-3 Cleanup Levels - Ecological - Soil
L-4 Cleanup Levels - Ecological - Surface Water
L-5 Cleanup Levels - Ecological - Sediment
M-l Landfill Lobes ARARs - Chemical Specific
M-2 Landfill Lobes ARARs - Action Specific
M-3 Landfill Lobes ARARs - Location Specific
M-4 FDDA ARARs - Chemical Specific
M-5 FDDA ARARs - Action Specific
M-6 FDDA ARARs - Location Specific
M-7 GSA ARARs - Chemical Specific
M-8 GSA ARARs - Action Specific
M-9 GSA ARARs - Location Specific
M-10 DGGW ARARs - Chemical Specific
M-l 1 DGGW ARARs - Action Specific
M-12 DGGW ARARs - Location Specific
-------
ROD RISK WORKSHEET
Table G-1
Summary of Chemical of Concern and Medium-Specific Exposure Point Concentration
Scenario Timeframe: Future
Medium: Soil
Exposure Medium: Upland Soil (0-10')
Exposure Point
Chemical of
Concern
Concentration Detected
Minimum
Maximum
Units
Frequency of
Detection
Exposure Point
Concentration
Exposure Point
Concentration
Units
Statistical
Measure
(1)
QSA. Upland
Benzo(a)artthracene
0.046
45
mg/kg
10/13
380
mg/kg
95% UCL
Benzo(a)pyrene
0.042
27
mg/kg
10/13
22.8
mg/kg
95% UCL
Benzo(b)fluoranthene
0.066
19
mg/kg
10/13
16.1
mg/kg
95% UCL
Benzo(k)fluor3rittiene
0,08
24
mg/kg
8/13
20.27
mg/kg
95% UCL
Dibenz(a.h)anthfacene
0.068
4,5
mg/kg
5/13
3.882
mg/kg
95% UCL
!ndeno(1,2,3-cd)pyrene
0.11
10
mg/kg
9/13
8.49
mg/kg
95% UCL
Key
(1) Statistics: Maximum Detected Value (Max); 95% UCL (95% UCL); Arithmetic Mean (Mean)
GSA = Garage and Storage Area (Group 4)
The table represents the future chemicals of concern (COCs) and exposure point concentrations (EPCs) for each of the COCs detected in upland soil (i.e., the concentrations that wilt be used to estimate the exposure and
risk for each COC in upland soil). The table includes the range of concentrations detected for each COC, as well as the frequency of detection (i.e., the number of times the chemical was detected in the samples
collected at the site), the EPC, and how the EPC was derived. Thrs table indicates that the carcinogenic PAHs benzo(a)anlhracene, benzo(a)pyrene, denzo(b)fluoranthene, benzo(k)fluorarrthene. dibenz(a,h)anthracene,
and indeno(1,2,3-cdJpyrene are the only COCs in upland soil at the site. The 95% UCL on the arithmetic mean was used as the EPC for these six carcinogenic PAHs.
Source: A Guide to Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1899)
Page 1 of 1
Section G Tables-HH draft.xls
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ROD RISK WORKSHEET
Table G-2
Summary of Chemical of Concern and Medium-Specific Exposure Point Concentration
Scenario Timeframe: Future
Medium: Groundwater
Exposure Medium: Indoor Air
Exposure Point
Chemical of
Concern
Concentration
Detected
Minimum
Maximum
Units
Frequency of
Detection
Exposure Point
Concentration
Exposure Point
Concentration
Units
Statistical
Measure
d)
FFDA
Toluene
0.32
78DQ0
ug/l
9/24
8300
ug/m
Max
Xylenes (total)
0.43
282D0
ug/L
10/24
2500
ug/m'5
Max
Key
(1) Statistics: Maximum Detected Value (Maxjr95% UCL (95% UCL); Arithmetic Mean (Mean)
FDDA = Former Drum Disposal Area (Group 3)
The table represents the future chemicals of concern (COCs) and exposure point concentrations (EPCs) for each of the COCs for the vapor intrusion (i.e., indoor air) pathway that were detected in groundwater (i.e., the
concentrations that will be used.to estimate the exposure and risk for each COC for the vapor intrusion pathway). The table includes the range of concentrations detected for each COC, as well as the frequency of
detection (i.e., the number of times the chemical was detected in the samples collected at the site), the EPC, and how the EPC was derived. This table indicates that the volatile organic chemicals, toluene and xylenes,
are the most frequently detected COCs in groundwater that may potentially impact indoor air at the site. The maximum detected groundwater concentration was used to estimate a maximum indoor air concentration that
was used as the EPC for each of the COCs selected for the vapor intrusion pathway.
Source: A Guide to Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999)
Page 1 of 1 Section G Tables-HH draft.xls
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ROD RISK WORKSHEET
Table G-3
Summary of Chemical of Concern and Medium-Specific Exposure Point Concentration
Scenario Timeframe: Future
Medium: Groundwater
Exposure Medium; Potable Groundwater
Exposure Point
Chemical of
Concern
Con ce rttra tion Detects
Units
Frequency of
Detection
Exposure Point
Concentration
Exposure Point
Concentration
Units
Statistical
Measure
m
Minimum
Maximum
Groups f 4 2
1,2-Dicttoraet hane
2
e.b
ug/L
2/73
6.9
ug/L
Max
i.2-QH*ieroe«iene (total)
150
150
ug/L
1 /8
150
ug/L
Max
1,2-Dictilon3 pro pane
0.37
34
ugO.
2/73
3.4
ug/L
Max
1,4-Dichloroben^e ne
0.48
11
ugflL
20/74
11
uft/L
Max
1 ,4-CHiicane
2.2
830
ug/L
40/53
830
ug/L
Max
2'Bwlanone
17
27000
ug/L
21/65
27000
ug/L
Max
i-Methyl-2-penianone
10
13000
ug/L
28/65
13000
ug/L
Max
Acetone
2.5
21000
ug/L
25/65
21000
uga.
Max
Benzene
0.31
36
ug/L
28 69
34
ugfl.
Max
CMorofonm
1.7
1.7
ug/L
1/73
1 ?
US/L
Max
cis-1 ,2-DicMoroel hene
0.47
450
ug/L
20/M
450
U9/L
Ma*
Ethyibenzene
1.3
2000
ugfl.
32/74
2000
ug/L
Max
Methylene
0.42
2140
ug/L
8/72
2140
ug/L
Ma*
a- Propylbensene
0.42
260
ug/L
14/63
260
ug/L
Max
Telrichlefoethene
0,72
17
ug/L
3/72
17
ug/L
Max
Tetrahydntfuran
2.5
10000
U$/L
40/57
10000
ug/L
Max
Toluene
353
21000
ug/L
39 /?e
21000
ug/L
Max
Tnchioroelhene
1.1
78
uq/l
0/74
76
ug/L
Max
Vinyl Ghkrfde
1
35
ug/L
4/72
35
ug/L
Mix
Xytenas (total)
036
490
ug/L
46/78
400
ug/L
Max
3-/4-Meifty1phenol
6,6
1000Q
ugA.
20/se
10000
ug/L
Max
4-Uefhy^hend
6600
11000
ug/L
4/a
11000
ug/L
Max
NapMhatene
0.4®
240
ug/L
15/77
240
ug/L
Max
N-NI?rc*Qdhfvbuty1aethyi-2-
penianone, bert2ene, ethylberuene tetrafrydrofyran, toluene, xylenes arwl melhylphenols are the it>ost frequently detected COCs in groundwater at the srle. The maximum deleded concentration was used as the EPC
for each at (he COCs delected in groundwater
Source: A Guide to Preparing Superfund Proposed Plans* Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999)
Page 1 of 1
Section G Tabtes-HH draftxls
-------
ROD RISK WORKSHEET
Table G-4
Summary of Chemical of Concern and Medium-Specific Exposure Point Concentration
Scenario Timeframe; Future
Medium: Groundwater
Exposure Modium: Ptrtiblt Groundwater
Exposurt Point
Chemical of
Concern
Concentration Detected
Units
Fneqwency of
Detection
Exposure Point
Concentration
Exposure Point
Concentration
Units
SUtisticaf
Meatum
(13
Minimum { Maximum
Grcut* 3-6
1.1,2-tnchlartt'ine
0.29
44 4
U0fl_
21/131
444
ugt.
W*y
1,2-OichlotTjet*ene jlotal}
2
130
ug/L
2/4
130
Mftl
Max
1 .Z-OieNcroproean e
0.35
39
ug*l
I'll 8
36
uOl
May
1,4-0»d*onjt*Niz«ne
CM
32
uoA.
iome
32
u»l
Max
i,*-Obothv»
t.e
3000
u®L
58/120
3000
xlQ?l
Max
2&Jt»non«
22
77000
ugfL
10*126
771»0
vq/L
Max
4»Metti|4-2'pentanone
1
190000
ugfl.
15/12?
190000
vgfL
Max
Acetone
2.1
73000
ogfl.
16/125
73000
v&L
Max
AetytaMrte
300
1300
ugfl_
3/2*
1300
Max
Qenzenc
0.12
45
ugft.
39/131
45
U0/1
Max
Cartxm TetracNonde
52
52
ugiL
1/93
52
ugfL
Max
Chtortriaim
0 28
57
uai.
2/106
5?
Max
®-1.2 -OKhkHUflUtei*
019
220
uglL
42/127
220
Ufl/t
Max
Etnyl methacrylete
AGOG
4000
ua/t
1/2*
4000
liflA.
Max
ESiy^tjenzena
004
MOO
UJIL
3S/148
6400
ug/L
Max
MettiftenH cfttawde
0 55
zm
ugA.
6(130
2200
ug?L
Max
n-PrcpyfeamzerM
0 99
82
u qiL
24/115
92
USML
Max
TatracHoRMrthenfl
023
U8
Xytmm
0 3
2B200
u^ciuetHefta, eth^j^nienf tWahy^rcftj^an toluftfte, and rnethylpfienols are the meet traqu>efldy detected COC® in gfaundwater it eaefi cf the CQCs detectac! in grGuncfcvste<
Source: A Guide ia Preparing Superfund Proposed Plans, Records -of D«tfcs>on, and Other Remedy defection Decision Documents. i(U,S. EPA, 1*tS}
Page 1 of 1
Section G Tables-HH draft,:
-------
ROD RISK WORKSHEET
Table G-5
Cancer Toxicity Data Summary
Pathway: Ingestion, Dermal
Chemical of
Concern
Oral Cancer
Slope Factor
Dermal Cancer
Slope Factor
Slope Factor
Units
Weight of
Evidence/Cancer
Guideline Description
Source
Date
(MM/DD/YYYY)
1.1 2-T nchioroelhane
5 7E-02
5 7E-02
(mg/kg-dayf
c
IRIS
Q3/07/Q7
1.1-Dichloroe thane
N/A
N/A
N/A
c
N/A
N/A
1.2-DrcnioroelhanB
9 1E-02
S.1E-02
(mg/kg-day)"'
32
IRIS
03/07/07
1 2-Dichloroetherie (total)
N/A
N/A
N/A
N/A
N/A
N/A
1 2-DicttlOropropane
6 86-02
i.ae-02
(mgfcs-day)-1
N/A
HEAST
1997
1 4 - D icfi'arcbenzBn b
24E-02
2.4E-02
(mgfcg-dayj'
N/A
HEAST
1997
1,4-DJOxane
1.1E-02
1.1E-Q2
(rng/kg-day)"
B2
IRIS
03/07/07
2-Butanone
N/A
N/A
NIA
N/A
N/A
N/A
4-MeIhyl-2-penlanor>9
N/A
N/A
N/A
N/A
N/A
N/A
Acetone
N/A
N/A
N/A
N/A
N/A
N/A
Acrylonjfiile
5 4E-01
5.4E-01
(mglkg-dayf
B1
IRIS
03/07/0?
Benzene
5 5E 02
5.5E-02
(mg/kg-dey)"1
A
IRIS
03/Q7/O7
Carbon Tetrachloride
1 3E-01
1.3E-01
(mg/kB-deiy)''
82
IRIS
03/07/07
Chloroform
3.1E-02
3.1E-D2
(mg/kg-day)1
B2
CalEPA
2005
cis-l ,2-DiChloroelhenB
N/A
N/A
N/A
Q
N/A
N/A
Ethyl methacrylate
N/A
N/A
N/A
N/A
N/A
N/A
Ethylbenzere
N/A
N/A
N/A
0
N/A
N/A
Methylene chloride
7.5E-G3
7.5E-03
(mg/kj-day)'1
B2
IRIS
03/07/07
rvPrGpyibemene
N/A
N/A
N/A
N/A
N/A
N/A
T etr.jichEoroeih6n6
-5 4E-C1
5.4E-01
Img/kg-jay)"'
B1
CalEPA
2005
Tetrahydrofuran
N/A
N/A
N/A
N/A
N/A
N/A
Toluene
N/A
N/A
N/A
N/A
N/A
N/A
Trchiofoelhene
4 0E-01
4 0E-01
(mgftg-day)"
N/A
EPA
2001
Vmy" Chloride - adult
7.2E-01
7.2E-01
(mgfto-day)"
A
IRIS
03/07/07
Vinyl Chloride - lifetime
1.5E+0Q
1.5E+0G
(mg/kg-day)"
A
IRIS
03/07/07
Xylenes (total)
N/A
N/A
N/A
N/A
N/A
N/A
2-Mathyiphenoi
N/A
N/A
N/A
G
N/A
N/A
3-/4Mgthytphenol
N/A
N/A
N/A
N/A
N/A
N/A
4-Methyi phenol
N/A
N/A
N/A
C
N/A
N/A
Benza(aianUiracene
7.3E-01
7.3E-01
(nig/kg-day)''
N/A
IRIS {23
03/07/07
Benzo(a)pyr©ne
7.3E*00
7-3E+00
(mg/kg-day)"
B2
IRIS
03/07/07
Benja(b)fluaranthene
73E-C1
7.3E-01
(mg/kg-day)"'
B2
IRIS {2}
03/07/07
Bervzo(k)fluDranthere
7 3E-02
7.3E-02
(rng/kg-day)"
B2
IRIS (2)
03/07/07
bi s(2-Eihylhexyl)ph(hatate
1 4E-G2
1.4E-02
(mg/kg-day)M
B2
tRIS
03/07/0?
Dibenz(a,h)anlhracen©
7.3E+00
7 3E+DQ
(m^kg-day)"
82
IRIS {2)
03/07/07
indeno(1,2,3-cd)pyren»
73E-01
7.3E-01
{mg/kg-day)"
B2
IRIS f2>
03/07/0 7
Naphthalene
N/A
N/A
N/A
c
N/A
N/A
N-NHrosodi-n-butyiamine
54E+00
5.4E+00
pg/Kg -day)'
B2
IRIS
03/07/07
N-Niirosopyrrolidine
2.1E+00
21E+00
{mg/kg-day)"'
B2
IRIS
03/07/07
o-TouKJine
2.4E-01
2.4E-G1
(mg/kg-day)"'
N/A
HEAST
1997
Phenol
N/A
N/A
N/A
D
N/A
N/A
Pyrdine
N/A
N/A
N/A
N/A
N/A
N/A
alpha-BHC
6.3E+00
8 3E+00
£mg/kg-day)"'
B2
IRIS
03/07/07
Arociof-1254 {water}
40E-01
4 0E-01
{mg/kg-day)'1
B2
IRIS
03/07/07
Antimony
N/A
N/A
N/A
N/A
N/A
N/A
Arsenic
1.5E+00
1.5E-+00
{mg/kg-day)"'
A
IRIS
03/07/07
Be^llium
N/A
N/A
N/A
B1
N/A
N/A
Cadmium
N/A
N/A
N/A
B1 (via inhalation)
N/A
N/A
Chromium
N/A
N/A
N/A
A (via inhalation)
N/A
N/A
Manganese
N/A
N/A
N/A
D
N/A
N/A
Siiver
N/A
N/A
N/A
D
N/A
N/A
Thallium
N/A
N/A
N/A
D
N/A
N/A
Zinc
N/A
N/A
N/A
D
N/A
N/A
Pathway: inhalation
Chemical of
Concern
Unit Risk
Units
Inhalation
Cancer Slope
Factor
Units
Weight of
Evidence/Cancer
Guideline Description
Source
Date
(MIWDD/YYYY)
1,1.2-Trichloroethane
1.6E-05
{UQfrnV
5.6E-02
(mg/kg-day)'1
c
IRIS*
03/07/07
1,1-DiChlofoefhans
N/A
N/A
N/A
N/A
c
N/A
N/A
1.2-Dichioroethane
2.6E-05
lug/rn^)1
9 1E-02
(mg/kg-day)"'
B2
IRIS*
03/07/07
12-Dichioroethene (total)
N/A
N/A
N/A
N/A
N/A
N/A
N/A
1,4-Oioxane
7.7E-OS
(ugflrt3)"1
2,7E-02
{mg/kg-day)''
B2
CalEPA*
2005
2-Butanone
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Page 1 of 2 Section G Tables-HH draft xls
-------
ROD RISK WORKSHEET
Table G-5
Cancer Toxicity
Data Summary
4-Methyi-2 pemancne
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Acelone
N/A
N/A.
N/A
N/A
N/A
N/A
N/A
Acryionitnie
8 BE-05
(ugW}"1
2.3BE-01
(mg/kg-day)"1
S1
IRIS
03/07/07
Benzene
7,BE-06
(ug/m3)'1
2.73E-02
(mg/kg-day)"1
A
IRIS*
03/07/07
Carton Tetrachloride
1.5E-0S
[ug/rn3}'1
5.25E-02
(mg/kg-day)'1
B2
IRIS*
03/07/07
Chloroform
2.3E-05
(ug/rn3f
8Q5E-02
(rng/kg-day)"1
32
IRIS*
03/07/07
cis-1,2-Dichionoethene
WA
M/A
N/A
N/A
D
N/A
N/A
Ethyf melhacryiate
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Ethyibenzena
N/A
N/A
N/A
N/A
D
N/A
N/A
Methylene chlonda
4.7E-0?
(ug/m3)"1
1.65E-03
(rng/kg-day)"'
82
IRIS*
03/07/0?
n-PiDpyltienzens
N/A
N/A
N/A
N/A
N/A
N/A
N/A
TetrachlorGethene
59E-06
(ug/rn3)"1
2076-02 ,
(rng/kg-day}'1
01
CaiEPA
2005
Tetrahydrofuran
n/a
N/A
N/A
N/A
N/A
N/A
N/A
Toluene
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Tricnioroelhene
2 0E-06
(ug/m3}*1
7.00E+00
(mg/kg-dayr'
N/A
CaiEPA
20G5
Vinyl Chloride - adult
4.4E-06
iuOfmY
1.54E-02
(mg/kg-^ayr1
A
IRIS"
03/07/0?
Vinyl Chioride - lifetime
8.6E-06
lug/m3}1
3.QBE-Q2
(rng/kg-day)"1
A
IRIS*
03/07/07
Xylenes (total)
WA
N/A
N/A
N/A
N/A
N/A
N/A
2-Methylphenol
N/A
N/A
N/A
N/A
C
N/A
N/A
3-/4 Methyiphenol
WA
N/A
N/A
N/A
N/A
WA
N/A
4-Methyiphenoi
WA
N/A
N/A
N/A
C
WA
N/A
Dis(2-Em/ihexyi)pinma)ate
2 4E-06
(ug/m3)*1
8 4E-03
(rng/kg-day)"1
B2
CaiEPA
20G5
.Naphtha; ene
N/A
N/A
N/A
N/A
C
N/A
N/A
NNtrosodi-n-butylamine
1 6E-03
(ug/m3)'1
S.8E+0Q
img/kg-da?)'1
02
IRIS*
03/07/07
N-Nitrosopyrrolicine
6 1E-C4
(ug/rn3) *
2.14E*0Q
img/kg-day)"'
B2
IRIS*
Q3/07/07
Phenol
N/A
N/A
N/A
N/A
D
N/A
N/A
Pyridine
N/A
WA
N/A
N/A
N/A
N/A
N/A
Key
EPA Group
n/a Not applicable
A - Human carcinogen
iRiS integrated RisK Information System, U S. EPA.
81 - Probable human carcinogen - Indicates that limited human data are available
hEAST = National Center for Exposure Assessment, Health Effects
62 - Probable human carcinogen - indicates sufficient evidence in animals and inadequate or no
Assessment Summary Tables
evidence in humans
CaiEPA - Cairfomsa Environmental Pnoleclion Agency
C - Possible human carcinogen
P - Not classifiable as
a human carcinogen
(2} me foltowng toxicity equivalency factors (TEFs) were applied to the
E - Evidence of noncarcinogenicity
toxicrty value for benzo(a)pyrene to derive a to*iaty value for carcinogenic
PAHs
' - indicates slope factor calculated from unit risk; SF =
70 kg / 20 rnV'UR
Sen 2 o( a)a n thr acene 0.1
Benzo(a)pyrene 1
BenzoCbjfiuoranlhene D.1
Berizo(k)fluoramhene DQ1
Di be riz( a, h}ant hrace ne 1
indeno{1t2,3-cd5pyrene 0 1
Tnis table provides me carpnagaciic risk information which is relevant to tha contaminants of concern in upland soil, indor air, and groundwater. At this time, slope factors are not available for the dermal route
of exposure Thus, the dermal stape factors used in ihis assessment have been extrapolated from oral values An adjustment factor is sometimes applied, and is dependent upon how welt the chemical is
absorbed via the oral route Adjustments are particularly important for chemicals with less than 50% absorption via the ingestion route. However, adjustment ss not necessary for the chemicals evaluated at
this s^e Therefore, the same values presented above were used as the dermal carcinogenic slope factors for these contaminants, Fifteen of the COCs are also considered carcinogenic vta the inhalation
route Araclor 1254. aipha-SHC. and arsenic, as non-volatile contaminants, wane not included in the evaluation of inhalation axpcsunu.
Source: A Guide to Preparing Superfund Proposed Plan*, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999)
Page 2 of 2
Section G Tables-HH draftxls
-------
ROD RISK WORKSHEET
Table G-6
Non-Cancer Toxicity Data Summary
Pathway; Ingestion, Darmaf
Chemical of Concern
Chronic/
Subchronlc
Oral RfD Value
Oral RfD
Unit#
Dermal RfD
Dermal RfD
Unit#
Primary Target Organ
Combined
Uncertainty/
Modifying
Factors
Sources of RfD:
Target Organ
Dates of Rfd:
Target Organ
(MM/DD/YYYY)
1 1,2-T richloroetft a na
Chronic
4.0E-O3
mg/kg-day
4.0E-03
mg/kg-d«y
Blood
1QOO
IRIS
03/07/0?
l.l-Dichloroethane
Chronic
2.06-01
mg/kg-day
2.OE-01
mg/kg-day
CNS
PFRTV
01/27/05
1,2-OfcWoroemane
Chronic
2 OE-01
mg/kg-day
20E-01
mg/kg-day
Kidney
300
AT SDR MRL
(intermediate)
09/01/01
1.2-Dichloroathene (total)
Chronic
8.0E-03
mg/kg»day
8.0E-03
mg/kg-day
Liver
HEAST
1997
1 2-DcWoropropane
Chrome
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
1 4-D(cniofODenzsne
Chronic
9 0E-O2
mg/kg-day
g.OE-02
mg/kg-day
Developmental
tooo
IRIS m
03/07/0?
1.4-0iQ*ane
Chronic
1 0E-01
mg/kg-day
1.OE-01
mg/kg-day
Livar
100
ATSDR MRL
10/01/04
2-fititafione
Chronic
e oe-oi
mg/icg-day
6.0E-01
mg/kg-day
Developmental
1000
IRIS
03/07/07
4 Mi?ihyl-2-pBnt3none
Chronic
8 OE-02
mg/kg-day
aoe-02
mg/kg-day
liver. Kidney
3000
HEAST
1987
Acsione
Chronic
9 01-01
mg/kg-day
9.oe-oi
mg/kg-day
Kidney
1000
IRIS
03/07/07
Acryiorutrile
Chronic
1.QE*03
mg/kg-day
t .0E-03
mg/kg-day
Reproductive
1000
HEAST
1997
Benzane
Chronie
4.GE-G3
mg/kg-day
4 0E-03
mg/kg-day
Immune System
300
IRIS
03/07/07
Carbon Tetrachloride
Chronic
7.0E-04
mg/kg-day
7.0E-04
mg/kg-day
Liver
1000
!RIS
03/07/07
Chloroform
Clonic
1.0E-D2
mg/kg-day
1 0E-Q2
mg/kg-day
Liver
100
\ms
03/Q7/07
as-1.2-Dichtoro8thene
Chronic
1.0E«D2
mg/kg-day
1.0E-02
mg/kg-day
Blood
PPRTV
03/D1/06
Ethyl rnethacrylate
Chronic
9 OE-02
mg/kg-day
5.0E-02
mg/kg-day
Kidney
10D
HEAST
1997
Elhylbe^zene
Chrome
1.QE-01
mg/kg-day
1.OE-01
mg/kg-day
Liver; Kidney
1000
IRIS
03/07/07
Methyiane chloride
Chronic
$ OE-02
mg/kg-dey
6.0E-02
mg/kg-day
Uver
100
IRIS
03/07/07
n-Propylbenzene
Chronic
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Teirachioroethene
Chrome
1 0E-C2
mg/kg-day
10E-02
mg/kg-day
Uvir
1000
IRIS
03/07/07
Tetrahydrofuran
Chrome
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Toluene
Chronic
8 OE-02
mg/kg-day
' 8.0E-Q2
mg/kg-day
Kidney
3000
IRIS
03/07/07
Tncnioroethane
Chrome
N/A
N/A
N/A
WA
N/A
N/A
N/A
N/A
Vmy! Chlonde
Chronic
3.0E-C3
mg/kg-day
3.0E-O3
mg/kg-day
Liver
3G
IRIS
03/07/07
Xylenes (total)
Chrome
2.0E-01
mg/kg-day
2.0E-Q1
mg/kg-day
General Toxicity
1000
IRIS
03/07/07
2-Melhylphenol
Chronic
5 0E-02
mg/kg-day
5.DE-02
mg/kg-day
General Toxicity; CNS
1000
IRIS
03/07/07
3-/4-Methyfphenol
Chronic
S.OE-02
mg/kg-day
5.06-02
mg/kg-day
General Toxicity: CNS
1000
IRIS (value for 3-
methylphenol) '
03/07/07
4-Methylphenol
Chronic
5.0E-02
mg/kg-day
5.0E-02
mg/kg-day
General Toxicity; CNS
1000
IRIS (valua fer3-
methylphenofj
03/07/07
Be n 2 o (a j anthracene
Chronic
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Benzo{ajpyrene
Chronic
HIA
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Benzo(biflyi3raniher»e
Chronic
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
BenzoSkJfluorantftene
Chronic
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
b'x(2-Ethy!h»xyl)phlha>®i«i
Chronic
2.0E-Q2
mg/kg-dey
2.OE-02
mg/kg-day
Liver
10QQ
IRIS
03/07/07
Ciberi^la.hianthracene
Chronic
Ni'A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
>rvdeno( t .2 3-cd)pyr«ne
Chronic
N/A
N/A
N/A
Ni'A
N/A
N/A
N/A
N/A
Maphthaene
Chrome
2 OE-02
mg/kg-dey
2 GE-02
mg/kg-day
General Toxicity
300Q
IRIS
03/07/0?
N-Nitrosodi-n-buiylsinme
Chronic
N>A
N/A
N/A
N/A
N/A
N/A
N/A
NfA
N- Ni Uo scpyrro' id
Chronic
N/A
HIA
N/A
N/A
N/A
N/A
N/A
N/A
O-Tpiyidine
Chronic
WA
HIA
N/A
N/A
N/A
N/A
N/A
N/A
Phenol
Chronic
3.0E-01
mg/kg-day
3.0E-01
mg/kg-day
Developmental
300
IRIS
03/07/07
Pyridine
Chronic
1 OE-03
mgCkg-day
1.0E-03
mg/kg-day
Liver
1GG0
IRIS
03/07/07
alpha-BHC
Chronic
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Afocor.1254
Chronic
2-0E-05
mg/kg-day
2 0E-D5
mg/kg-day
Immune system
300
JRIS
03/07/07
Antimony Chronic
4.0E-04
mg/kg-day
6 OE-OS
mg/kg-day
General Toxicity
1000
IRIS
03/07/0?
Arsenic Chronic
30E-Q4
mg/kg-day
3.0E-04
rng/kg-day
Skirt
3
IRIS
03/07/07
Beryllium ; Chronic
2.GE-03
mg/kg-day
1.4E-0S
mg/kg-day
Gastrointestinal System
300
IRIS
03/07/07
Cadmium 1 Chronic
5.0E-Q4
mg/kg-day
25E-D4
mg/kg-day
Kidney
10
IRIS
03/07/07
Chromium Chronic
3.0E-03
mg/kg-day
7.SE-Q5
mg/kg-day
Q»stro
-------
ROD RISK WORKSHEET
Table G-€
Non-Cancer Toxicity Data Summary
Pathway: Inhalation
Chemical of Concern
Chronic/
Subchronic
Inhalation RfC
Inhalation
RfC Units
Inhalation
RfD
Inhalation RfD
Unita
Primary Target Organ
Combined
Uncertainty/
Modifying
Factor#
Sources of RfC;
RfD; Target
Organ
Oats s
(MM/DD/YYYY)
1 1.2'TnchloroathBne
Chronic
14
ug/fns
N/A
N/A
Blood
N/A
Calculated <1>
N/A
1.1-Oichbroelhane
Chronic
50
ug/m3
N/A
N/A
Kidney
N/A
HEAST
199?
1 2-Dichloroelhane
Chronic
2430
ug/m3
N/A
N/A
Uver
90
ATSDR MRL {0 6 ppm)
2005
1.2-Dichtofoethene (total)
Chronic
60
ug/m3
N/A
N/A
Respiratory system; liver
N/A
PPRTV (value for
trans isomer)
03/01/06
1.4-Dioxani
Chronic
3000
ug/m3
N/A
N/A
Developmental
N/A
CalEPA REL
09/21/06
2-Sutanone
Chronic
5000
ug/m1
N/A
N/A
Developmental
300
IRIS
03/07/07
4-Methyi-2-pemanona
Chronic
3000
ug/m3
N/A
N/A
Developmental
300
IRIS
03/07/07
Acetone
Chronic
3150
ug/m3
N/A
N/A
Kidney
N/A
Calculated (1)
N/A
Acryionitnle
Chronic
3.5
ug/m3
N/A
N/A
Respiratory system
1000
IRIS (value for
isoprepylbenzene;
calculated from RfD)
omm?
Benzene
Chronic
30
ug/m3
N/A
N/A
immune System
300
IRIS
03/07/07
Carbon Tetrachloride
Chronic
2.45
ug/m3
N/A
N/A
Uver
N/A
Calculated (1)
N/A
Chloroform
Chronic
300
ug/m3
N/A
N/A
Kidney; developmental
gastrointestinal system
N/A
CalEPA REL
09/21/06
cs-1 2-Dichlcraeth#ne
Chronic
GO
ug/m3
N/A
N/A
Respiratory system; liver
N/A
PPRTV (value for
trans isomer)
03/01/06
Ethyl meihacryiate
Chronic
m
ug/m3
N/A
N/A
K>dney
N/A
Calculated (1)
N/A
Ethyiberszene
Chronic
1000
Uj/fTI3
N/A
N/A
Developmental
300
IRIS
03/07/07
Methylene chloride
Chronic
3000
ug/m3
N/A
N/A
Liver
100
HEAST
1997
n-Propylbenzene
Chi^n ic
140
ug/m3
N/A
N/A
N/A
N/A
Calculated (1)
N/A
TetrBChloroelhene
Chronic
35
ug/m3
N/A
N/A
CNS; respiratory system
N/A
CalEPA REL
01/17/06
Tetfahydrofuran
Chronic
301
ug/m3
N/A
N/A
h/A
N/A
Calculated (1)
N/A
Toluene
Chrome
5000
ug/m3
N/A
N/A
CNS
10
IRIS
03/07/0?
T riehioroelhene
Chronic
600
ug/m5
N/A
N/A
CNS
N/A
CalEPA REL
09/21 /OS
Vmyl Chloride
Chronic
100
ug/m3
N/A
N/A
liver
30
IRIS
03/07/07
Xylenes (total) | Chronic
too
ug/m3
N/A
N/A
CNS
300
IRIS
03/07/07
!
2-Methylphenol Chrome
175
ug/m3
N/A
N/A
General Toxicity; CNS
N/A
Calculated (H
N/A
3-/4-Methytphena! Chronic
17.5
ug/m3
N/A
N/A
General Toxicity, CNS
N/A
Calculated (1)
N/A
4-Matftyt phenol Chronic
17.S
ug/m3
N/A
N/A
General Toxicity; CNS
N/A
Calculated (1)
N/A
bi 5t2-Ethylhexyl)ph?.halaie 1 Chronic
70
ug/m3
N/A
N/A
Liver
N/A
Calculated (1)
N/A
Naphthalene I Chronic
3
ug/m3
N/A
N/A
Respiratory system
3000
IRIS
03/07/07
N-NitfOSOdi-n-butjianrne
Chronic
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N-Niirosopyrrolidine
Chronic
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Phenol
Chronic
200
ug/m'
N/A
N/A
Gastrointestinal system,
cardiovascular, CNS, kidney
N/A
CalEPA REL
09/21/00
Pyridine
Chrome
3.5
ug/m5
WA
WA
Liver
N/A
Calculated f1j
N/A
Key
N#A - No information available ATSOR MRL ~ Agency for Toxic Su balances and Disease Registry, Minimum Risk Levels
IRIS - integrated Risk Informal ton System, US EPA HEAST = National Cenisr for Exposure Assessment. Health Effects Assessment Summary Tables
PPRTV = Provisional Peer-Review Toxicity Values, obtained From Superfund Technical Support Center
CalEPA = California Environmental Protection Agency. REL = Reference Exposure Level
<1) - RfC calculated from me oral RfD or. if no oral RID was available from the inhalation RfD provided in the EPA Regan i PRO labia (October 200*) RfC = RfDi * (70 kg 120 m3/day>
(2> RID for 1.2-dchiaroberzene used ss surrogate
(3) - A modifying factor of 3 was applied to the oral RID for manganese io account far drinking water exposures, in accordance with EPA IRIS Recommendations
This table provides non-carcinogenic risk information which is relevant fo the contaminants of concern in upland coil, indoor air, and groundwater. Thirty-eight of the COCs have oral toxicity date indicating their potentiai far
adverse non-carc.no9er.1c health effects m humans. Chronic and subchronic toxicity data available for the thirty-eighl COCa tor oral exposures have been used to develop chronic oral reference dosea (RfDs), provided in
this iaoie The available chronic and subchronic toxicty data indicate that benzene and Arodor-1264 affect the immune system, 1.2-dichloroethana, 1.4-dioxane, 4 -m a thyt- 2- p entanone. 6is<2-elhy1heKy1)pbthalate, carbon
leiracWondc, chloroform, ethylbenzene. methylene cNonde, tetrachloroelhene, vinyl chonde. and pyridine affect 1he liver, 1,1,2-lrichloroelhane, cis-1,2-diehlonoelhene, lhailium, and zmc affect the blood. 1,2-dichioroethane,
4-methyl-2-peniflr>one, acetone, ethyl methacrytate, ethyl ben2ene, toluene. and cadmium affect the kidney, xylene*, methyl phenols, naphthalene, and antimony are general systemic toxicant*. 1,1-diehioroethene,
memyiphenols. and manganese affect the central nervous system. 1,4-dicWorobanztwi#, 2-butanone, and phenol are developmental toxicants, acrykmiinl* affects reproduction, beryllium and chromium affect the
gasirainlast.na! system, and arsenic and silver affect the skin Reference doses are not available for berizo(a )on1 h raoene, benzofejpyrene, benzo(b)fhjoren1hene, benzo(kjfluoranthen», dibenz(a,h)anthrHcene,
>ndeno{1,2,3-cd)pyrene. 1,2-dichlorpfopana, n-propylbentene. letrahydrofuran. trichloroaihene. ^nltrosodt-n-bulylamine, N-nftrosopyrrolkline, cMoluidine, and alpha-BHC OermaJ RfDs are not available for any of ihe COCs
As was !he case for the carcinogenic data, dermal RfDs can be extrapolated from oral WDs by applying an adjualrrwil Factor 83 appropriate. Onl RfDs ware acfju&iBd for COCs with iess than 50% absorption via Ihe
ingestion roule (antimony, beryllium, cadmium, chromium, manganese, and silver) to derive dermal RfDs for these COCs delation reference concentrations (RfCs) are avadabie for thirty volatile COCs evaluated for me
inhalation pathway Aroclor-1254. alpha-BHC, antimony, arsenic, beryllium, cadmium, chromium, manganese, silver, thallium, and zinc as non-volatile contaminants, were not included in the evaluation of inhalation
exposures
Sources A Guide lo Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999)
Page 2 of 2
Section G Tables-HH draft xls
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ROD RISK WORKSHEET
Table G-7
Risk Characterization Summary
- Carcinogens
Scenario Timeframe: Future
Receptor Population: Resident
Receptor Age: Young Child/Adult
Medium
Exposure
Medium
Exposure Point
Chemical of
Concern
Carcinogenic Risk
Ingestion
Inhalation
Dermal
External
{Radiation)
Exposure
Routes Total
Soil
Upland Sort (0-W)
GSA, Upland
Benzo(a)anthracene
Benzo(a)pyrene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Dibenz(a,h)anthracene
lndeno{1,2.3-cd)pyrene
6E-05
4E-04
3E-05
3E-Q6
6E-05
1E-05
--
3E-Q5
2E-04
1E-05
1E-06
36-05
6E-06
--
9E-05
5E-04
4E-0S
5E-06
9E-05
2E-05
Upland Soil Risk Total =
' 8E-04
Total Risk =
8E-04
Key
-- Route of exposure is not applicable to this medium.
GSA = Garage and Storage Area (Group 4}
This table provides risk estimates for the significant routes of exposure for the future child and adult resident at the GSA. These risk estimates are based on a reasonable maximum exposure and were developed by
taking into account various conservative assumptions about the frequency and duration of a child's and adult's exposure to upland soil, as well as the toxicity of the COCs (benzo(a)anthracene. benzo{a)pyrene,
benzo(b)flLioranlhene. benzo(k)fluoranthene, dibenz(a,ti)anthracene, and indeno(1,2,3-cd)pyrene). The total risk from direct exposure to contaminated upland soil at this site to a future child and adult resident at the GSA
is estimated to be 8 x 10"4. The COC contributing most to this risk level is benzo{a)pyrene in upland soil. This risk level indicates that if no clean-up action is taken, an individual would have an increased probability of 8
in 10,000 of developing cancer as a result of site-related exposure to the COCs.
Source: A Guide to Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999)
Page 1 of 1
Section G Tables-HH draftxts
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ROD RISK WORKSHEET
Table G-8
Risk Characterization Summary - Non-Carcinogens
Scenario Timeframe; Future
Receptor Population: Resident
Receptor Age; Young Child/Adult
Medium
Exposure
Medium
Exposure Point
Chemical of
Concern
Primary Target Organ
Non-Carcinogenic Hazard Quotient
Ingestion
Inhalation
Dermal
Exposure Routes
Total
Groundwater
Indoor Air
FDDA
Toluene
Xylenes (total)
CNS
CNS
2E+00
2E+01
2E+00
2E+Q1
Indoor Air Hazard Index Total:
3E+01
CNS Hazard Index ¦
3E+01
Key
n/a - Toxicity criteria are not available to quantitatively address this route of exposure,
- Route of exposure is not applicable to this medium.
FDDA = Former Orum (Disposal Area (Group 3)
This table provides hazard quotients (HQs) for each route of exposure and the hazard index (sum of the hazard quotients) for all routes of exposure for the future adjacent resident exposed to groundwater that may impact indoor
air via vapor intrusion. The Risk Assessment Guidance (RAGS) for Superfund states that, generally, a hazard index (HI) of greater than 1 indicates the potential for adverse noncancer effects. The estimated target organ HI of
30 indicates that the potential for adverse effects could occur from exposure to indoor air containing toluene and xylenes.
Source: A Guide to Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999)
Page 1 of 1
Section G Tables-HH draft.xls
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ROD RISK WORKSHEET
Table G-9
Risk Characterization Summary
- Carcinogens
Scenario Timeframe: Future
Receptor Population: Resident
Receptor Age: Young Child/Adult
Medium
Exposure
Medium
Exposure Point
Chemical of
Concern
Carcinogenic Risk
Ingestion
Inhalation
Dermal
External
(Radiation)
Exposure
Routes Total
Groundwater
Potable Groundwater
Beneath Landfill Lobes
(Groups 1 & 2}
1,2-Dichloroethane
1,2-Dichloroprapane
1,4-Dichfor©benzene
1,4-Dioxane
Benzene
Chloroform
Methylene chloride
Tetrachloroethene
Trichloroethen©
Vinyl Chloride
1E-Q5
4E-06
4E-D6
2E-04
3E-Q5
9E-07
3E-D4
2E-Q4
5E-04
9E-04
5E-05
N/A
N/A
6E-05
1E-04
IE-OS
3E-04
3E-05
5E-05
1E-Q4
4E-07
3E-07
2E-06
4E-Q7
4E-06
6E-08
BE-OB
7E-05
7E-05
4E-05
--
6E-05
4E-06
7E-0S
2E-04
1E-04
1E-Q5
6E-04
3E-04
6E-04
1E-03
N-Nrtrosodi-n-butylamine
N-NHrosopyrrofidine
o-Toluidine
1E-04
3E-Q4
1E-05
3E-Q4
5E-07
N/A
5E-06
2E-06
4E-07
--
4E-04
3E-04
IE-OS
Arsenic
5E-02
--
2E-04
--
5E-02
Groundwater Risk Total =
5E-02
Total Risk"
SE-02
Key
- Route of exposure is not applicable to (his medium.
N/A - Toxicity criteria are not available to quantitatively address this route of exposure.
— Route of exposure is not applicable to this medium.
This table provides risk estimates for the significant routes of exposure for the future child and adult resident exposed to groundwater used as household water should groundwater COCs migrate from beneath the
landfill lobes (Groups 1 & 2). These risk estimates are based on a reasonable maximum exposure and were developed by taking into account various conservative assumptions about the frequency and duration of a
child's and adult's exposure to groundwater, as wall as the toxicity of the COCs (1,2-dichtoraethane, 1,2-dichloropropane. 1,4-dichlorobenzene, 1,4-tJioxane, benzene, chloroform, methylene chloride, tetrachloroethene,
trichloroethene. vinyl chloride. N-nrtrosodi-n-butylamino, N-nitrosopyrroitdine. o-toluidine, and areenic), The total risk from direct exposure to contaminated groundwater at this site to a future resident, in the event that
groundwater migrates from beneath the landfill lobes, is estimated to be 5 x 1Q7. The COCs contributing most to this risk level are 1,4-dioxane, benzene, methylene chloride, tetrachloroethene, vinyl chloride. N-nrtrosodi
n-butylamlne, N-nitrosopyrrolidine, and arsenic in groundwater. This risk level indicates that if no clean-up action is taken, an individual would have an increased
probability of 5 in 100 of developing cancer as a result of site-related exposure to the COCs in groundwater.
Source: A Guide to Preparing Superfund Proposed Plans, Records of Decision* and Other Remedy Selection Decision Documents (U.S. EPA, 1999)
Page 1 of 1
Section G Tables-HH draft.xls
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ROD RISK WORKSHEET
Table G-10
Risk Characterization Summary - Non-Carcinogens
Scenario Timeframe: Future
Receptor Population: Resident
Receptor Age: Young ChildlAduit
Medium
Exposure
Exposure Point
Chemical of
Primary Target Organ
Non-Carcinogenic Hazard Quotient
Medium
Concern
Ingestion
Inhalation
Dermal
Exposure Routes
Total
Groundwater
Potable Groundwater
Beneath Landfill Lobes
(Groups 1 & 2}
1,2-Dichloroethene (tola!)
Liver
1E+00
3E+0C
7E-Q2
4E+00
2-Gutanona
Developmental
4E+QQ
1E+QQ
2E-02
5E*00
4-Methyt- 2 -pentanone
Liver; Kidney
1E*Qi
2E*00
4E-Q1
2E+01
Acetone
Kidney
2E*00
2E+0Q
1E-02
4E+00
Benzene
Immune System
BE-D1
2E+D0
7E-02
2E+00
ciS-1,2-Dichloroethene
Blood
4E+00
9E+QQ
5E-01
tE+01
Ethytbensene
Liven Kidney
2E*00
2E+D0
6E-01
SE+00
Methane chloride
Liver
M*QQ
BE-01
6E-02
4E+00
n-Prapylberuene
N/A
N/A
5E+00
N/A
5E+00
T^trahydrafuran
N/A
N/A
4E*01
N/A
46+01
Toli>ef>e
Kidney
2E*01
SE+DO
4E+0Q
3E+01
Xylenes (totaf)
General Toxicity
2E-01
m+QQ
1E-01
66*00
3-M-Melhylphanol
General "Toxicity: CNS
2€*Qli
4E+Q0
9E-01
2E+0!
4-MethyIphenoI
General Toxicity; CMS
2£H>1
4E+DQ
1E+00
2£*0?
Naphthalene
General Toxicity
1E+00
6E*01
4E-Q1
8E+01
Pyridine
Uver
4E+Q0
9E-01
7E-02
4G+00
Arsenic
Skin
0E+02
,,
2E+00
8£*02
Beryllium
Gastrointestinal System
1 E*00
--
SE-01
2E+00
Cadmium
Kidney
6E+01
—
4E+O0
6E+01
Manganese
CNS
4E+Q1
«
3E+00
4E+01
Thallium
Blood
5F+00
1E-Q2
5E+00
Groundwater Hiani Index Total ¦
9E+02
General Toxicity Hizard Index =
1E*02
Developmental Hazard index »
5E*CX3
Gastrointestinal System Hazard tadex *
2E*«J
Immune System Hazard Index c
2E+0G
Liver Hazard Index *
3E+01
Kidney Hazard Index ¦
1E*02
Blood Hazard Index*
2E+0?
Skin Hazard index'
6E+Q2
CNS Hazard Index*
8E+Q1
Key
N/A - Toxicity criteria are not available to quantitatively address this route pf exposure
- Rome of exposure is not applicable to thrs medium
This table provide* naxard quotianis (HQs) for each route of exposure and Ihe hazanj index {sum of the hazard quotients) far all routes of exposure forthe Mure resident exposed to groundwater used as household waier
should groundwater COCs migrate from beneath the landfill lobes {Groups 1 & 2). The Risk Assessment Guidance (RAGS) for Superfund slates that, generally, a hazard index (HI) of greater than 1 indicates the potential for
adverse noncancet electa The estimated target organ His between 2 and 900 indicate that Ihe potential for adverse effects cowrfd occur from exposure to contaminated groundwater containing t ,2-dichioroelhene. 2-
birlafions, 4-methyf-2-pentanene. acetone, benzene, ns-1.2-d ichoroelhene, ethyl benzene, methylene chloride, n-propylbenzene, twtfahytjrofuran, toluene, xylenes, rnethylphenols. naphthalene, pyridine, arsenic, beryllium.
cadmmm manganese, and thallium
Source: A Guide to Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.$. EPA, 1999}
Page 1 of 1
Section G Tables-HH draft.xls
-------
ROD RISK WORKSHEET
Table G-11
Risk Characterization Summary
- Carcinogens
Scenario Timeframe: Future
Receptor Population: Resident
Receptor Age: Young Child/Adult
Medium
Exposure
Medium
Exposure Point
Chemical of
Concern
Carcinogenic Risk
Ingestion
Inhalation
Dermal
External
(Radiation)
Exposure Routes
Total
Groundwater
Potable Groundwater
Outside landfill Lobes
(Groups 3-6)
1,1,2-Trichloroethane
1,2'Dichioroeihane
1,2-Dtchloropfopane
1,4-Didhloro benzene
1,4-Diexane
AcryloniWIe
Benzene
Carbon Tetrachloride
Chloroform
Methylene chloride
Tetrachloroetfiene
Trichloroethene
Vinyl Chloride
alpha-BHC
Aroclar-1254
7E-06
7E-05
4E-06
1E-06
5E-04
16-02
4E-05
1E-04
3E-06
3E-04
5E-05
4E-05
2E-03
5E-06
SE-06
3E-05
3E-04
N/A
M/A
2E-04
1E-02
1E-04
2E-Q4
4E-05
3E-04
1E-05
4E-06
2E-04
5E_o7
3E-06
3E-07
7E-07
2E-06
1E-04
SE-06
2E-05
2E-07
8E-06
3E-05
6E-06
7E-05
1E-06
NE
-
3E-05
4E-04
4E-D6
2E-06
8E-04
2E-02
2E-04
4E-04
4E-0S
6E-04
9E-05
5E-Q5
2E-03
6E-06
8E-06
bis(2-Ethy1hexyl)phthalale
1E-04
1E-07
2E-04
--
3E-04
Arsenic
6E-Q2
2E-04
-
©E-02
Groundwater Risk Total *
9E-02
Total Risk ¦
9F-02
Key
- Route of exposure is not applicable to this medium.
N/A - Toxicity criteria are not available to quantitatively add/ess this route of exposure.
NE = Not evaluated
This table provides risk estimates for the significant routes of exposure for the future child arid adult residents exposed to Groups 3-6 groundwater used as household water. These risk estimates are based on a
reasonable maximum exposure and were developed by taMng into account various conservative assumptions about the frequency and duration of a child's and adulfs exposure to groundwater, as wefl as the toxicity of
the COCs (1.1,2-tiichIoroethane, 1,2-dichtoroetfiane, 1,2-dichloropropane, 1,4-dichlorobenzene. 1,4-dioxane, acrylonitrife. benzene, carbon tetrachloride, chloroform, methylene chloride, tetradhloroeihene, trichloroethene,
vinyl chloride. alpha-BHG, b\s{2~etlryftrexy()ptrthalate, Arodor-1254, and arsenic). The total risk from direct exposure to contaminated groundwater at this ste to a hitoe resident is estimated to be
9 x 102. The COCs contributing most to this risk level are 1,2-dichloroe thane. 1,4-dioxane, acrylonitrte, benzene, carbon tetrachloride, methylene chloride, vinyf chloride, bis(2-ethylhexyl)phthalate, and arsenic in
groundwater. This risk level indicates that if no dean-up action is taken, an individual would have an increased probability of 9 in 100 of developing cancer as a result of site-related exposure to the COCs in
groundwater.
Source: A Guide to Preparing Superfurtd Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999)
Page 1 of 1
Section G Tables-HH draft.xls
-------
ROD RISK WORKSHEET
Table G-12
Risk Characterization Summary - Non-Carcinogens
Scenario Timeframe: Future
Receplor Population: Resident
Receptor Age: Young ChildfAduft
Mecfcum
Exposure
Expoit/r* Paint
Chemical of
Primary TitgefOngin
IMon-GsifcMagenlc MaztrtJ Ouotienf
Medium
Concern
Ingestion
Inhalation
Dermul
Exposure Routes
Total
PiMMSnwxMftir
Outvda Landfill tcow
t&Qut* 3-ti)
1 .'Dtchttrortur*
CNS
2E*O0
ae«oo
se-cc
1E-01
1 J-DreNcroiAPi torW7*»
RaercducA*
1E<5
2E-HX?
Btn31
3E-02
Banana
hwrwrw System
se-oi
2E<0
te-01
3t^
Ctrfer fcrfrotam*
Lav
6E«00
2E*Ol
1E«00
1E*01
c»-1 2-0eMErc*«w»
Stood
2E*«1
4E*00
IE-01
6E*QD
Ethyl mefheanffces
Kit**y
¦te-KXJ
>E
%*oa
36-01
9E-0?
4E*0B
rvPrspyiMnean*
H/A
N/A
2E*0Q
N/*
SE'OO
T#tr*rdne*ren
WA
N/A
9E
2EHD
-<.2-4feN»X»aw*, «*-?< limC g»yfe«n;»ng, cfrlpntft). ninyilWiri. t»trahyfrphir»n, drtlcnfo. xyfen«« (BWJ}, matfy*phenOiC, r«sWh»l»n«. phenol ,
Aracfor-125
-------
ROD RISK WORKSHEET
Table G-13
Risk Characterization Summary
• Carcinogens
Scenario Timeframe; Future
Receptor Population: Facility Worker
Receptor Age: Adult
Medium
Exposure
Medium
Exposure Point
Chemical of
Concern
Carcinogenic Risk
Ingestion
Inhalation
Dermal
External
(Radiation)
Exposure
Routes Total
Groundwater
Potable Groundwater
Outside Landfill Lobes
(Groups 3-6)
1,1,2-T richloroeltiane
1,2-Diehloroethane
1,4-Dioxane
Acrylonitrile
Benzene
Carbon Tetrachloride
Methylene chloride
Tetrachtoroethene
Trichloroethene
Vinyl Chloride
Arodor-1254
bis(2-Ethylhexyt)phthalate
Arsenic
2E-06
2E-05
1E-0*
3E-03
1E-05
3E-D5
7E-0S
1E-05
1E-05
2E-04
2E-06
3E-05
1E-02
--
5E-oa
3E-07
2E-07
9E-06
SE-07
2E-06
8E-07
2E-06
5E-07
3E-06
NE
2E-05
2E-06
--
2E-06
?E-05
1E-04
3E-03
1E-0S
3E-05
7E-C5
2E-05
1E-05
2E-04
2E-06
5E-Q5
1E-02
Groundwater Risk Total =
2E-02
Total Risk ¦
2E-02
Key
- Route of exposure is not applicable to this medium,
N/A - Toxicity criteria are not available to quantitatively address this route Of exposure.
NE = Not evaluated
This tabie provides risk estimates for the significant route* of exposure for future facility workers exposed to Groups 3-6 groundwater used as potable water. These risk estimates are based on a reasonable maximum
exposure and were developed by taking into account various conservative assumptions about the frequency and duration of an adutt worker's exposure 1© groundwater, as well as the toxicity of the COCs (1,1,2-
trichtoroethane, 1,2-dichioroethane, 1,4-dioxane, saytonitnle, benzene, carbon tetrachloride, methylene chloride, tetrachtoroethene, trichloroethene, vinyl chloride, Aroctof-1254, bis(2-ethylhexyl)phthalate, and arsenic).
The total risk from direct exposure to contaminated groundwater at this sits to future facility workers Is estimated to be 2 x 10"J. The COCs contributing most to this risk level are 1,4-dioxane, acrylonitrile, vinyl chloride,
and arsenic in groundwater. This risk level indicates that if no clean-up action is taken, an individual would have an increased probability of 2 in 100 of developing cancer as a result of site-related exposure to the COCs
in groundwater.
Source; A Guide to Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999)
Page 1 of 1
Section G Tables-HH draft xls
-------
ROD RISK WORKSHEET
Table G-14
Risk Characterization Summary - Non-Carcinogens
Scenario Timeframe: Future
Receptor Population: Facility Worker
Receptor Age: Adult
Medium
Exposure
Exposure Point
Chemical of
Primary Target Organ
Non-Carcinogenic Hazard Quotient
Medium
Concern
Ingestion
Inhalation
Dermal
Exposure
Routes Total
Groundwater
Potable Groundwater
Outside Landfill Lobes
(Groups 3-6)
4-Methyl-2-pentanone
Liver, Kidney
3E*01
4E-01
3E+01
Aerylonrt rite
Reproductive
1E-KJ1
--
SE-02
1E+01
Toluene
Kidney
1E+01
--
1E+Q0
1E+01
Xylenes (total)
General Toxicity
2E+00
--
4E-01
2E-00
Antimony
General Toxicity
3E-K50
..
3E-03
3E+00
Arsenic
Skin
9E-H31
1E-02
9E+01
Beryllium
Gastrointestinal System
3E-H30
..
7E-Q2
3E+00
Manganese
CNS
7E+QG
--
3E-02
7E+00
Stiver
Skin
2E+QQ
--
4E-03
2E+00
Zinc
Blood
2E+QQ
--
2E-04
2E+DQ
Groundwater Hazard Index Total ¦
2E+02
General Toxicity Hazard Index =
SE+00
CNS Hazard Index =
7E+00
Gastrointestinal System Hazard Index =
3E+00
Liver Hazard index *
3E+Q1
Kidney Hazard Index =
4E+01
Blood Hazard Index =
2E+QG
Skin Hazard Index -
9E+Q1
Reproductive Hazard index =
1E+Q1
Key
N/A - Toxicity criteria are not available to quantitatively address this route of exposure.
- Route of exposure is not applicable to this medium.
This table provides hazard quotients (HQs) for each route of exposure
and the hazard index (sum of the hazard quotients) for all routes of exposure for future facility workers exposed to Groups 3-6 groundwater used as
potable water. The Risk Assessment Guidance (RAGS) for Superfund states that, generally, a hazard index (HI) of greater than 1 indicates the potential for adverse noricancer effects. The estimated target organ His betweer
2 and 200 indicate that the potential for adverse effects could occur from exposure to contaminated groundwater containing 4-methyi-2-pentanone, acrylonrtrile, toluene, xylenes, antimony, arsenic, beryllium, manganese,
silver, and zinc
Source: A Guide to Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999)
Page 1 of 1
Section G Tables-HH draft.xls
-------
ROD RISK WORKSHEET
Table G-15
Risk Characterization Summary - Non-Carcinogens
Scenario Timeframe: Future
Receptor Population; Facility Worker
Receptor Age: Adult
Medium
Exposure
Medium
Exposure Point
Chemical of
Concern
Primary Target Organ
Non-Carcinogenic Hazard Quotient
Ingestion
Inhalation
Dermal
Exposure Routes
Total
Air
Indoor Air
FDDA
Xylenes (total)
CNS
6E+G0
6E+0Q
tndoor Air Hazard Index Total!
6E+O0
CNS Hazard Index =
6E+00
Key
N/A - Toxicity criteria are not available to quantitatively address this route of exposure.
- Route of exposure is not applicable to this medium.
FDDA = Former Drum Disposal Area (Group 3)
This table provides hazard quotients (HQs) for each route of exposure and the hazard index (sum of the hazard quotients) for all routes of exposure for future FDDA facility workers exposed to groundwater that may Impact indooi
air via vapor intrusion. The Bisk Assessment Guidance (RAGS) for Superfund states that, generally, a hazard index (HI) of greater than 1 indicates the potential for adverse n on cancer effects. The estimated target organ HI of 6
indicates that tie potential for adverse effects could occur from exposure to indoor air containing xylenes.
Source: A Guide to Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Decision Documents (U.S. EPA, 1999)
Page 1 of 1
Section G Tables-HH draft.xls
-------
Table G-16
Occurrence, Distribution, and Selection of Chemicals of Concern (COPCs)
Study Area: Sutton Brook Disposal Area Site - Upper Sutton Brook
Medium: Surface Water
Chemical1
Frequency
of Detection
Maximum
Detected
Concentration
ML)
Location of
Maximum
Detected
Cone,
Screening
Toxicity
Value
("g/L)
Screening
Toxicity
Value
Source
HQ
COPC?2
Reason
for
Exclusion
4,4-DDT
1 17
0.009
SW-05 (99)
0.001
1
9
Yes
alpba-BHC
1 n
0.006
SW-05 (99)
2.2
2
<1
No
BSV
1,3-Diehlorobenzene
1/8
1
SW-05 (99)
71
2
<1
No
BSV
bis(2-Ethylhexyl)phthalate
1/8
1
SW-05 (99)
3
2
<1
No
BSV
1,2,4-Trimethylbenzene
3/5
7.7
SW-33
77
3
<1
No
BSV
Ethyl benzene
4/8
12
SW-05 (99)
7.3
2
1.6
Yes
Isopropylbenzene
2/5
1.16
SW-33
255
3
<1
No
BSV
n-Propylbenzene
2/S
1.27
SW-33
128
3
<1
No
BSV
o-Xylene
3/5
13.6
SW4-99
13
2
1.0
Yes
p/m-Xylene
3/5
36.5
SW4-99
13
- 2
3
Yes
Toluene
5/8
123
SW4-9S
9.8
2
13
Yes
Xylenes (total)
2/4
37
SW-05 (99)
13
2
3
Yes
Barium, Dissolved
3/3
80
SW-33
4
2
20
Yes
Iron, Dissolved
3/3
1400
SW 32 (04)
1,000
1
1.4
Yes
Manganese, Dissolved
3/3
530
SW-33
120
2
4
Yes
Zinc, Dissolved
3/3
32
SW-33
89
1a
<1
No
BSV
Notes:
1 Chemicals identified in the SLERA with maximum detected concentrations exceeding screening criteria or considered bioaceumulative were evaluated in the BERA.
2 Analytes were selected in the BERA as contaminants of potential concern (COPCs) if the maximum HQ exceeded 1.0
HQ - Hazard Quotient {ratio of the maximum detected concentration to the screening toxicity value)
COPC - Contaminant of potential concern
BSV - Below Screening Value
Screening toxcrty values sources:
1. National Ambient Water Quality Criterion (NAWQC) (USEPA I986a,b; 1987; 1992a. 1998,2002.2006)
1a. Metals criteria were adjusted to a site-specific hardness value of 72 mg/L as CaC03 using equations provided in USEPA, 2006.
2. Secondary Chronic Value (SCV) as presented in Suter and Tsao (1996)
3. USEPA Region 6 Eco.'ogical Screening Levels tor Surface Water (freshwater)
Page 1 of 1
Section G Tables-Eco-0815Q7d.xls [G-16J
-------
Table G-1J
Occurrence, Distribution, and Selection of Chemicals of Potential Concern (COPCs)
Study Area: Sutton Brook Disposal Area Site - Upper Sutton Brook
Medium: Sediment
Chemical1
Frequency
of
Detection
Maximum
Detected
Concentration
(mg/kg)
Location of
Maximum
Detected
Cone.
Screening
Toxicity
Value
(mg/kg)
Screening
Toxicity
Value
Source
HQ
COPC?2
Reason
for
Exclusion
4,4-DDE
1 / 9
0,0018
SD-21 {99}
37,431
1
<1
No
BSV
Endosulfan II
1 19
0,0018
SD-21 {99}
0.029
1
<1
No
BSV
2-Methylphenol
1/9
0.24
SD-21 (99)
0.134
1
1.8
Yes
3-/4-Methylptienol
1/4
1.2
SD-33 (04)
0.627
1
1.9
Yes
Benzo{a)pyrene
1/9
0.44
SD-14 (99)
0.257
1
1.7
Yes
bi s(2-Ethylhexy!)phthalate
2/9
6.4
SD-33 (04)
11.534
1
<1
No
BSV
Di-n-octyl phthatate
1 / 9
0.65
SD-33 (04)
100.213
1
<1
No
BSV
1,2.4-T rimethylbenzene
4/8
3
SD-22 (99)
1.287
1
2
Yes
1,3,5-Trimethyibenzene
4/8
16
SD-23 (99)
1.163
1
14
Yes
4-Methyl-2-pentanone
2/8
0,1
SD-21 (99)
0,043
1
2
Yes
Acetone
4/8
0.72
SD-14 (99)
0.069
1
10
Yes
Carbon disulfide
2/8
0.015
SD-22 (99)
0.001
1
15
Yes
Chloroethane
3/8
0,085
SD-23 (99)
0.026
1
3
Yes
Ethylberizene
5/8
3.3
SD-22 (99)
0,088
1
38
Yes
Isopropylbenzene
6/8
0.58
SD-32 (04)
4.855
1
<1
No
BSV
Naphthalene
5/9
1.5
SD-32 (04)
0,514
1
3
Yes
n-Butylbenzene
1/8
0.13
SD-33 (04)
2,913
1
<1
No
BSV
n-Prapylbenzene
6/8
0.69
SD-32 (04)
2.848
1
<1
No
BSV
o-Xylene
5/8
0.57
SD-33 (04)
0.134
1
4
Yes
p/m-Xylene
6/8
10
SD-22 (99)
0,134
1
75
Yes
p-lsopropyltoluerte
4/8
0.14
SD-33 (04)
21.249
1
<1
No
BSV
sec-Butylbenzene
1/8
0.005
SD-22 (99)
3.017
1
<1
No
BSV
Toluene
5/9
4.8
SD-33 (04)
0.061
1
79
Yes
Arsenic
10/10
767
SD-15 (99)
8.2
2
94
Yes
Cadmium
2/10
0.44
SD-33 (04)
1.2
3
<1
No
BSV
Page 1 of 2
Section G Tables-Eco-081507d.xls [G-17]
-------
Table G-17
Occurrence, Distribution, and Selection of Chemicals of Potential Concern (COPCs)
Study Area: Sutton Brook Disposal Area Site - Upper Sutton Brook
Medium: Sediment
Maximum
Location of
Screening
Screening
Chemical1
Frequency
Detected
Maximum
Toxicity
Toxicity
Reason
of
Concentration
Detected
Value
Value
HQ
COPC?2
for
Detection
(mg/kg)
Cone.
(mg/kg)
Source
Exclusion
Iron
10/10
85300
SD-15 (99)
20000
4
4
Yes
Lead
8/10
120
SD-33 (04)
46.7
3
3
No
AVS/SEM
Manganese
10/10
550
SD-33 (04)
460
4
1.2
Yes
Mercury
1 110
0.11
SD-15 (99)
0.15
3
<1
No
BSV
Zinc
9/10
240
SD-33 (04)
150
3
1.6
No
AVS/SEM
Notes:
1 Chemicals identified in the SLERA with maximum detected concentrations exceeding screening criteria or considered bieaccumulative were evaluated in the SERA.
2 Analytes were selected in the BERA as contaminants of potential concern (COPCs) if the maximum HQ exceeded 1.0
HQ - Hazard Quotient (ratio of the maximum detected concentration to the screening toxicity value).
BSV - below screening value
AVS/SEM - Shown by AVS/SEM methods to not be bksavailable at this site
COPC - Contaminant of potential concern
Screening toxcity values sources:
1. Calculated by equilibrium partitioning as per USEPA, 1993, based on TOC of 2.33%,
2. USEPA Region 6 Ecological Screening Levels for Sediment
3. NOAA Effects Range-Low (ERL) (Buchman, M R., 1989)
4. Ontario Ministry of Environment and Energy Lowest Effect Level (LEL) (OME, 1996)
Page 2 of 2
Section G Tables-Eco-081507d.xls [G-17]
-------
Table G-18
Occurrence, Distribution, and Selection of Chemicals of Potential Concern (COPCs)
Study Area: Sutton Brook Disposal Area Site - Aquatic Wetland
Medium: Surface Water
Chemical1
Frequency
of Detection
Maximum
Detected
Concentration
(u g/L)
Location of
Maximum
Detected
Cone.
Screening
Toxicity
Value
(ug? L)
Screening
Toxicity
Value
Source
Amphib.
Screening
Criterion
(ug/L)
Amphib,
Screening
Criterion
Source
Max.
HQ2
COPC?3
Reason
for
Exclusion
Endosulfan I
1 /12
0.004
SW-02 (99)
0 058
1
NA
NA
<1
No
BSV
bis(2-Ethyihexyl)phthae surface water or amphibian endpoint
CQPC - Contaminant of potential concern
0SV - Below Screening Value
HQ - Hazard Quotient (ratio of tfie maximum detected concentration to Rve sereeninsg toxicity value}
Screening foxcity values sources;
1. National Ambient Water Quality Criterion (HAWQC) (USEPA 19S6a,t>; 19S7. 1992a, 1998, 2002,2006).
1 a- Metals criteria were adjusted to a site-specific hardness value of 72 mg/L as CaC03 using equations provided in USEPA, 2006.
2. Secondary Chronic Value (SCV) as presented in Suter and Tsao (1996)
3. USEPA Region 8 Ecofogicaf Screening Levels for Surface Water (freshwater)
4. Westerman, et at. 2003- Values shown are geometric mean of LC10 values
5. Birge. et al. 2000. LC50 value of 1.42 divided by 100 for NOEL use.
Page 1 of 1
Section G Tables-Eco-081507d.xls [G-18]
-------
Table G-19
Occurrence, Distribution, and Selection of Chemicals of Potential Concern (COPCs)
Study Area: Sutton Brook Disposal Area Site - Aquatic Wetland
Medium: Sediment
Chemical1
Frequency
of
Detection
Maximum
Detected
Concentration
(mg/kg)
Location of
Maximum
Detected
Cone.
Screening
Toxicity
Value
Ng/kg)
Screening
Toxicity
Value
Source
HQ
COPC?2
Reason
for
Exclusion
4,4-DDD
2/14
0.012
SD-16 (99)
0.427
1
<1
No
BSV
M'-DDE
3/14
0.0066
SD-24 {99)
406.051
1
<1
No
BSV
Benzo{a)pyrene
1/ 14
0.53
SD-01 (99)
2798
1
<1
No
BSV
BenzoicAcid
4/12
5,5
WS-104 (05)
0.155
1
35
Yes
bis(2-E!hyihescyi)phthaiate
4/16
3.8
WS-102 (05)
125.73
1
<1
No
BSV
1,2,4-Tnrnethyibenzene
5/15
0.035
SD-01 {99)
*4.035
1
<1
No
BSV
Acetone
18/21
2,1
WS-102 (05)
0.755
1
3
Yes
Chloroethane
7/27
D.35
SD-02(99)
0.263
1
1.3
Yes
tsopropylbenzene
5/18
0,35
WS-15((M)
52.93
1
<1
No
BSV
n-Bytyfbenzene
1/13
0.023
SD-24 (99)
31.758
1
<1
No
BSV
n-Propylbsnzene
3/14
0.075
WS-15 (04)
31.049
1
<1
No
BSV
p-Isopropy toluene
3/14
0.011
WS-tS (04)
231.639
1
<1
No
BSV
sec-Butytoe nzene
1 112
0.Q07
WS-15 (04)
32.887
1
<1
NO
BSV
Toluene
18/27
8.4
SD-02(99)
0.667
1
13
Yes
Afsenic
23/23
64
SD-38 (04)
8.2
2
8
Yes
Beryllium
11/22
2,1
WS-11 (04)
1,1
5
2
Yes
Cadmium
11/19
1.5
WS-11 (04)
1.2
3
1.3
No
AVS/SEM
Iron
22/22
24800
SD-01 (99)
20000
4
1.2
Yes
Lead
22/22
756
SD-01 (99)
40.7
3
1.6
No
AVS/SEM
Mercury
8/20
0.22
WS-102 (05)
0,15
3
1-5
Yes
Selenium
11/16
5.1
WS-11 (04)
072
5
7
Yes
Zinc
14M7
138
SD-01 (99)
150
3
<1
No
BSV
Notes:
1 Chemicals identified in the SLERA with maximum detected concentrations exceeding screening criteria or considered bioaccumutative were evaluated
2 Analytes were selected in the SERA as contamkiants of potential concern (COPCs) if the maximum HQ exceeded 1.0
in the BERA
HQ - Hazard Quotient (ratio of the maximum detected concentration to the screening toxicity value!
8SV - below screening value
AVS/SEM - Shown by AVS/SEM methods to not be bioamailable at this site
COPC - Contaminant of potential concern
Screening toxcity values sources:
1. Calculated by equilibrium partitioning as per USEPA, 1993, based on TOC of 25.4%.
2 USEPA Region 6 Ecological Screening Levels for Sediment
3. NOAA Effects Range-low (ERl) (Bgchman, M.R., 1999)
4. Ontario Ministry of Environment arxJ Energy Lowest Effect Level (LEL) (OWE. 1996)
5. Crommentuijn, 2000, Negligible effect concentration.
Page 1 of 1
Section G Tables-Eco-081507d.xls fG-19]
-------
Table G-20
Occurrence, Distribution, and Selection of Chemicals of Potential Concern (COPCsJ
Study Area: Sutton Brook Disposal Area Site
Medium: Wetland Soil
Chefnical1
Frequency
of
Detection
Maximum
Detected
Concentration
imglkg)
Location of
Maximum
Detected
Cone.
Screening
Tonicity
Value
(mg/kg)
Screening
Toxicity
Value
Source
HQ
COPC?3
Reason
for
Exclusion
4,4-ODO
2/9
0.044
SS-13 4W)
0 758
3
*1
No
BSV
A.A'-DDE.
2/8
0.0381
SS-13 !04)
0.S96
3
<1
NO
BSV
4,4'-DD7
1 (B
0 0C602
SS-13 J04}
0 0035
3
1 7
No
"
Aldrin
1/9
0.0051
SD-12 (99)
0 0032
3
1 6
Yes
&eii2o(a)artthracene
1 / 9
1.2
SD-12 (99)
1 2
S
1 0
No
BSV
Bertzo{a)pyrene
1/9
12
SO-12 (99)
1.2
S
1.0
No
BSV
8enzo(t>)fluefanfherte
1 /8
1.7
SO-12 (99)
1.2
6
1.4
Yea
Beruo(g, h ,i Jperylene
1 f 9
0.82
SO-12 (99)
1.2
e
<1
No
BSV
Beiizp(k^fluarantft«ne
1 .'9
0.58
SD-12 (99)
1.2
£
<1
No
BSV
Benzoic Ackj
2/8
0.78
SS-9 (04)
0.035
4
22
Yes
i^2-£th)rthixy!Jphihatatfi
1 /9
0.29
SS-13 (04)
100
5
<1
No
BSV
Chiysene
1 ?9
1.4
SO-12 (99)
1.2
3
1-2
Yes
Fkioranthsne
1 ^9
2.6
SD-12 (99)
1.2
6
2
Yea
tadenof t ,2.3-eri(pynsne
1 19
0.86
SD-12 (99)
t.2
8
<1
No
BSV
Paryterw
1 f 8
0.25
SS-9 (04)
1.2
6
<1
No
BSV
Phananthrene
1 (9
1.5
SD-12 (99)
1.2
6
1.3
Yes
Pyrene
1 / 9
2.3
SD-12 (99)
1.2
6
1.9
¥es
ZHescanone
1 / 8
00027
GP-23 (04)
89
3
<1
No
BSV
p-lttpepytohttne
1 /6
G.G1
GP-9 {D4J
52
4
<1
NO
BSV
Areenic
12 / 12
30
SS-9 (04)
18
%
1,7
Yes
Cadmium
7/12
1.2
WS-106 (05f
0.77
1
1.8
No
-
Lead
12/12
104
sd-12 im
56
1
1.9
No
-
Martggrteae
12/12
1000
WS-1Q7 <05J
415
7
2
Yes
Mercury
10/12
03
WS-106 <05)
0.00051
2
588
Yes
Selenium
9/12
24
WS-106 <0S)
0.21
2
11
Yes
Vanadium
12/12
16 1
$0-13(99)
2
5
8
Yes
Zinc
12/12
769
SD-12 (69)
120
1
<1
NO
BSV
Notes:
1 Ctiesrwcate identified tn the SLERA with maximum detected concentrations exceeding screening criteria or considered bioaocumulatwe were evaluated in the BERA.
? Analgias were selected in the BERA as contaminants of potential concern g Levels (Ec©~S$ls) (USEPA. 2003,2005) Lowest value listed. 2nd-lowesi: value for cadmium and lead are
shewn, amce lowest value « below 50th percentile of US background cooceniraliona. Value for 2iric ts draft.
2. Oak Ridge National Laboratory. 1997, Preliminary Remediatpon Goats for Ecological Erx*poinis This document lists the lowest wsfue for wildlife. plant
and invertebrates.
3. EPA Region 5,2003, Ecological Screening Levels Most of these values are based on bioaccumuiation.
4. No benchmarks available. Sedimert value used.
5 Efroymson, R.A.. et af. t99?. Toxica logical Benchmarks foe Screening Corttaminanls of Potential Concern for Effects on Terrestrial Plants
199? Revision Oak Ridge National Laboratory, Oak Ridge, Tennessee.
6 USEPA, 1999. Screening Level Ecological Risk Assessment Protocol for Waste Combusttoo Facililies. Draft Vol. 1-3 Appendix H-5-3G
All FAHs based on ber>zo{a)pvfene.
7, Paseh.ke, M.VY. etal 200S. Manganese toxicity thresholds for restoration grass species. Env Po» 13S{2) 313 322
Page 1 of 1
Section G Tabtes-Eco-081507d.xls [G-20]
-------
Table G-21
Occurrence, Distribution, and Selection of Chemicals of Potential Concern (COPCs)
Study Area: Sutton Brook Disposal Area Site - Pond
Medium: Surface Water
Chemical1
Frequency
of Detection
Maximum
Detected
Concentration
(ug/L)
Location of
Maximum
Detected
Cone.
Screening
Toxicity
Value
iugIL)
Screening
Toxicity
Value
Source
Amphib.
Screening
Criterion
(«g/M
Amphib.
Screening
Criterion
Source
Max.
HQ2
COPC?3
Reason
for
Exclusion
Barium, Dissolved
1 /1
6
SW-39 (04)
4
2
766
3
1.5
Yes
Manganese, Dissolved
1/1
20
SW-39 (04)
120
2
14.2
4
1,4
Yes
Zinc, Dissolved
1/1
7
SW-39 (04)
15.4
1a
3
3
2
Yes
Notes:
1 Chemicals identified in the SLERA with maximum detected concentrations exceeding screening criteria or considered bioaccumulative were evaluated in the BERA.
2 Maximum HQ is the higher of the two Hazard Quotients calculated for surface water screening criterion or the amphibian screening criterion
3 Anaiytes were selected in the BERA as contaminants of potential concern (COPCs) if the maximum HQ exceeded 1.0 for either the surface water or amphibian endpoint
COPC - Contaminant of potential concern
BSV - Below Screening Value
HQ - Hazard Quotient (ratio of the maximum detected concentration to the screening toxicity value).
Screening toxcity values sources:
1. National Ambient Water Quality Criterion (NAWQC) (USEPA 1986a,b; 1987; 1992a, 1998, 2002, 2006).
1a. Metals criteria were adjusted to a site-specific hardness value of 72 mg/L as CaC03 using equations provided in USEPA, 2006.
2. Secondary Chronic Value (SCV) as presented in Suter and Tsao (1996)
3. Westerman, et al, 2003. Values shown are geometric mean of LC10 values
4. Birge, et al. 2000. LC50 value of 1.42 divided by 100 for NOEL use.
Page 1 of 1
Section G Tables-Eco-081507d.xls [G-21]
-------
Table G-22
Occurrence, Distribution, and Selection of Chemicals of Potential Concern (COPCs)
Study Area: Sutton Brook Disposal Area Site - Pond
Medium: Sediment
Chemical1
Frequency
of
Detection
Maximum
Detected
Concentration
(mg/kg)
Location of
Maximum
Detected
Cone.
Screening
Toxicity
Value
(mg/kg)
Screening
Toxicity
Value
Source
HQ
COPC?2
Reason
for
Exclusion
Acetone
2/4
0.024
SD-42 (04)
0.0074
1
3
Yes
Carbon disulfide
2/4
0.0016
SD-39 (04)
0.0001
1
16
Yes
p-Isopropyltoluene
1 14
0.002
SD-39 (04)
2.28
1
<1
No
BSV
Arsenic
4/4
15
SD-39 (04)
8.2
2
1.8
Yes
Lead
4/4
31
SD-41 (04)
46.7
3
<1
No
BSV
Zinc
4/4
13
SD-39 (04)
150
3
<1
No
BSV
Notes:
1 Chemicals identified in the SLERA with maximum detected concentrations exceeding screening criteria or considered bioaccumulative were evaluated in the BERA.
2 Analytes were selected in the BERA as contaminants of potential concern (COPCs) if the maximum HQ exceeded 1.0
HQ - Hazard Quotient (ratio of the maximum detected concentration to the screening toxicity value).
COPC - Contaminant of potential concern
BSV - below screening value
Screening toxcity values sources:
1. Calculated by equilibrium partitioning as per USEPA, 1993, based on TOC of 2 33%.
2. USEPA Region 6 Ecological Screening Levels for Sediment
3. NOAA Effects Range-Low (ERL) (Buchman, M R., 1999)
Page 1 of 1
Section G Tables-Eco-081507d.xls [G-22]
-------
Table G-23
Occurrence, Distribution, and Selection of Chemicals of Potential Concern (COPCs)
Study Area: Sutton Brook Disposal Area Site
Medium: Upland Soil
Chemical1
Frequency
of
Detection
Maximum
Delected
Concentration
Cmg/fcgS
Location of
Maximum
Detected
Cone.
Screening
Toxicity
Value
(mg/kg)
Screening
Toxicity
Value
Source
HQ
COPC?2
Reason
for
Exclusion
¦M'-DDD
7/9
0.01
S0-04 (99)
0 75S
3
<1
NO
BSV
4.4" DOE
7/9
0.0086
SG-04 {59)
0.596
3
<1
NO
S5V
4.4--DOT
1/2
0.014
SO-07 m)
O.OQ3S
3
4
Yes
Aldrin
1 /8
0,00041
SO-1 Q
0.15
11
<1
No
BSV
delta-BHC
1 -;fi
a.0014
SO-09 <99>
0 004
3
<1
No
BSV
OiekJMrt
5/fl
0,0056
$0-09 {99)
0.011
1
<1
NO
esv
EndosuWarv iS
1/9
0.0013
SO-08 {99)
o.os
12
<1
No
BSV
Endrvt
3/?
0.0062
SO-09 {99)
0.0101
3
<1
No
BSV
End tin aldehyde
4/ B
0.OD21
SO-06 (99)
0.0105
3
<1
NO
BSV
Methoxyctilor
5/9
0.017
50-09 {99)
0 0109
3
<1
NO
BSV
Aroctof-124®
5/9
0.11
SQ-06 {99)
~.371
2
<1
No
BSV
Arocfcr-1260
8/9
D096
SO-04 (995
0,371
2
NO
BSV
1,2.4-T rtehlorobenzene
3/11
0.56
so-o ran}
0.4fi
9
1.2
Yes
2,4, &-Tnchlon^erKrf
2/10
0.39
SO-07 {99)
4
2
<1
No
BSV
2,4-Dimcehyfphenol
1/10
0.089
SCWJ7 {99)
0.01
3
9
Yes
2.6-DinrtroiOiuene
1 MO
0.22
SO-07 <99)
0.0328
3
7
No
-
2<:hlofonaphthatene
1 /10
0.19
SO-07 {99)
0.0122
3
16
No
-
2-Metty1n^rthaler>e
1!1U
0.2B
SO-09 {99)
1.73
10
<1
No
BSV
3J'-0icfttoraben2iCline
1 no
0.34
SO-08 {99)
0.0646
3
5
No
1/10
0.25
SO-07 {99)
0.15
4
1.7
Yes
Aoenaphthene
3/10
0.087
SO-10 {99}
1
9
No
BSV
Anthracene
6/10
Q.Z1
SO-07 {99)
9
No
BSV
8ei«o{p)anthracer»e
8/10
0.81
SO-09 {99)
12
8
<1
No
BSV
Benzo
-------
Table G-23
Occurrence, Distribution, and Selection of Chemicals of Potential Concern (COPCs)
Study Area: Sutton Brook Disposal Area Site
Medium: Upland Soil
Maximum
Location of
Screening
Screening
Chemical1
Frequency
Detected
Maximum
Toxicity
Toxicity
Reason
of
Concent radon
Detected
Value
Value
HQ
COPC?1
for
Detection
(•*9*9)
Cone.
{mg/kg}
Source
Exclusion
Ethytbenzene
2/11
8.2
se-3 (04)
32
9
1.9
Yes
FDDA
Isopropylbenzene
1/2
0.35
SB-3 (34)
1.06
10
NO
BSV
n-Btriyifcwiene
1/2
073
SS-3 (04)
1.06
10
<1
No
8SV
rv Propyl benzene
1/2
0.7
SB-3 (04)
1 06
10
<1
No
BSV
o-Xyier*
1 / 11
46
SB-3 (04)
1 06
10
4
Yes
FDDA
p/m-Xylene
2 f 11
20
se-3(04)
1.06
1D
19
Yes
FDDA
Xylene (total)
1/8
0.86
SO-09 (991
1 06
1D
<1
Yes
Model
p-lsopropytteluerie
1 12
037
" SB-3 (54)
52
S
<1
No
BSV
Toluene
4/11
65
SB-3 (04)
1 06
10
6
Yes
FDDA
Cadmium
6/11
063
SO-05 (99)
0.77
1
<1
No
BSV
Chromium
11 U
283
SG-G5 (99)
26
1
1.1
Yes
Copper
11 /11
883
SO-01 {99)
5D
6
IE
Yes
Lead
11/11
233
SO-01 (99)
56
1
4
Yes
Mercury
2/11
026
SB-? (04)
0.00051
2
510
Yes
Vanadium
11 M1
13
SO-07 (99)
2
7
9
Yes
Zinc
11 /11
379
SO-0? (99)
120
1
3
Yes
Notes:
' Chemicals identified in the SLERA with maxtmum delected concentrations exceeding screening criteria or considered bioaccumulative were evaluated in the BERA.
1 Analyses were selected in the BERA as ccmarrunants
of potential concern (COPCs) rf tie maximum HQ exceeded 1.0, except for anatyles designated wth
under Reason lor Exclusion These analogs were evaluated further in the SLERA utilizing site-specific modesng; comparison to receptor-specific benchmarks
resuhed in HQs beta* 1 0
HQ - Hazard Quotient (ratio of the maximum delected concentration to the &
creantng tonicity value).
BSV - btskm screening value
COPC - Contaminant of potential cor
icern
FDDA - Chemical selected as COPC in Former Drum ~
tsposalArea
N5V • No screening value available; low detection frequency and tow observed concentrations
Model - Selection of COPC is based
on SLERA calculat
ion of modeled maximum exposure » a carnivore (robin)
1. U5EPA Ecoiogkal Soil Screening levels (Eco-SSLs) {USEPA, 2003, 2DOS). Lowest value listed 2nd-lo*es
value for cadmium and lead are
shown, since lowest value is below 50th percentile of US background concentrations. Values for zinc and dieldrin are dr
aft
2 Oak Ridge National Laboratory, 1957 Preliminary R
emediation Goals tor Ecotogcal Endpoints, This document lists the lowest value for wHdtffe. plant.
3. EPA Region 5,2003. Ecological Screening Levels Most of these values are based o-i beaccumutation.
4. No benchmark available. Value based on 15 mg/kg LC5Q tor earthworm;
1 reported in the Hazardous Substance Database.
5 No benchmarks available Sediment value used
6 Efroymson. R.A. et al. 1997 Toxicoogtca! Benchmarks for Contaminants of Potential Concern for Effects on Soil and Litter 1
ivertebrates and
Heterotrophic Process: 1397 Revision. Oak Ridge Nat>onal Labors
rtory, Oak Ridge Te
nnessee.
7 Efroymson, R A, et al 1997 Toxcolagtcaf Benchmarks for Screening Contaminants of Potential Concern for Effects on Terrestrial Plants
1997 Revision. Oak Rtdge
National Laboratory Oak Rtdge, Tennessee
6 USE PA. 19&9. Screening Levei Ecological Risk Assessment Protocol tor Waste Canbostion
FaciWes. Draft Vol. 1-3 Append" H-5-30
All PAHs based on benzo(a}pyrene-
9. Huteebos, E.M. eial. 1993. Phytoto*ieity studies with Lactuca sativa in soil and nulnent solution Env To*. Chem 12(6}-107&-1094 EC50
values divided by 100
for NO A EL use, EiNytbertzene value based on styrene
10. Neuhauser, R. etal 1985 The toucrty of selected organic chemicals 1o the earthworm Eisenia fetida. J Environ. Qua!. 14(3J" 363-388 Study LC50S divided by 100
for NOAEL use. Values for alkylated benzenes are based on carbaryl, worm toxicities simitar
11 Calculated from lowest Ecotox value
12 Dutch Soil Intervention value, as
cited by the Risk
assessment information Sytemn (RA1S), endosutfan value based on endrin.
Page 2 of 2
Section G
Tables-Eco-08150Td.xls [G-23]
-------
Table G-24
Ecological Exposure Pathways of Concern
Exposure
Medi*
Sensitive |
Environment! Rec«tpfcar
Fllfl |
Y 6r M 1
Endangered*
Thwiterutd
Species Flag
YofM
Expoiuce I AaseMment
Routes I Endpointa
Meeeurement
6ntl points
UPPER SUTTON 8R00K HABITAT AREA
S«dmer>t
Senthsc
IcwttbtaEea
N
iage«tt3n ttsa sitmc
contact Ntti
chemc« in
eedimem
Sixwai and growth cf
ioc«f oopwiaticm o»
mrartabfetM
• CofnparKDn sadnanl CQPC
edncenii'a&tf!* » fttWuniM
- fyj*?^ ot i«din>ent to Hyitieaf Mm* «>vj
Cftmaxwws n the SouChan Tribulary
Surl#» aoter
N
P*J»g>e
myenety*r«. ana
ft»h pcputalara
N
tngeaiion and tSnac
contact w*r<
dwrnsaa in
turfaceweter
Survival arid oroWSh rf
potential fah and
ovftTMbiaia tanmuntwrn.
- C<*i^n&)n 0' «ai»f GOPO
wnceilraScma to cnWrtUfSanCurtartJ
" AQUATIC WETLAHD
Sed^erw
6e**<
inv«rhpt»*tee
N
Ingaabco a>xJ drac
cprtadwSfc
eftawneaia *i
eedmenl
Survival J(KlflKMithBl fff
bwtthc fiygnaiuialwi
COMTtMrilOM
- CwnearnoftotwwnewcOPC
a^nsentfetom »
Surlaca water
n
Pafegc
PC
eanaannaona Eb entanaAtafiehmaika
Surface **ter.
seckment. tra*
n
Avijn midlife
KieoK {carTw*q<*.
omfuvoea.
hoitwrt)
N
Dwtary Cxpotuiei
efCOPCs
Suaunacnuty (wvi»»
local popuyrtiofli of avian
Mid Ida
- Comparton of eu^
avian wkfrfa undi T1?A
SfTEPOND
Sediment
*
Sen**
ImvlBbraM*
N
Ingaahon and drac
contact wlh
ehemceta *1
eedmeni
Survival and ^rawtft d
bemhic ryrtatmUn.
cayrmjnW«
- Companion of sediment COPC
aanoemlrebomi ha bencfimartai
Siafaoa Hit
N
Pelage
mwwbniaa and
afnprfcian*
N
Ingaation and ine
canted wfth
cfcenucifc in
iJjtflCCwMtr
SufvniI and gravih of
ponnmi aiTspniettn »<*
irtv»tKra» aWHWlll
• Oxnpinrjc o< ayriaca walar COPC
oaiuwuuaaowa to cntanaftjanchinafta
Surface water.
l*da»&iily Csu daiaa n
l»«l I»«l«e «n«l TRVl,
, ¦ , wEToJm'Boiti'*.
"-)•¦¦_ . '
WeeendSo*
H
Tenvcn* Plant*
N
Uptake <*
cS*ermcal*«
MdMion
0»n*fiirty «r K
CeneNYaIrti
Watland So*
U
T*nrtttir«
Inyartabntai
N
ingrttwn and diwc
contact with
diefneala m *c«
Survrwa* and grmrift &
hwi—JjuM KiwMiaUaiet
fiomrrurtitiM
- Oynpan»on o) COPC coneaWKw s to
bonehnwii*
VWUrc So*
W
Wfliind
C*m»«9rci4 *4jii«
(Shns*i
N
Owtaiv aapoaunw
CiGOPCt
S\*a>."a!>lmr (suftuwaL
jrtiwPi. vp^ducsic) f*
iqci< (xpvmomd
camrearoia vnkUrk
¦ CsmpariacKiafMiRMriaddviary doa«s in
cjmwoiWt TRV»
Wrtaoo SOM
N
Wetland
iwttnreroMi weaitfa
•RaK*;
N
0ietfry e^ocuro
aiCQPC*
Suttmnteify (mrvrvSK
Biwrth wpioOucaon) C*
beaJ pepulalisns et
twrQtwomua wMW*
- Comparkon of estroated duKary dote* in
hert*>Ma »»tWirte witi TRV*
¦ s* w,.MMmww
Upland Soil*
N
Tcrrmtnai Plant*
N
Uptake erf
upland, to*
Diversity and abundaosa of
ta^resDMl ptanti
¦ CompjR»on of aol COPC cancantrvtkra to
CMH%timeflL|
Upland So«
N
TimiliHil
InwwtfcMet
N
iBgwMft and dntd
afrntawnh
chemicals r < oa
Suivwal and jrawti
WnwKnat rv»Tttfafa»*
ce«T>rMiti«a
• Qsmparaor of aM COPC roocani7at»fli to
bancrtmarkm
UpiaridSate
H
(Robn)
N
Oaui)i«««num
irfCGPC*
$v»Satnatiri(fr (suramai.
5^w6i raprcdiicbon) Oi1
local pcpUat»n of
uniMTyji Midirit
- Campareion dotet n
CamiViXiJiji wtl TRVl
Upar-JSo*
CJfTUV'DTDUl wfclllfe
(Meade*-Vote)
N
Dwiiry i^eiuni
ofCOPCs
SyibalnaUity {aurvivai.
^rowrn. nptaducaoni of
local p«£M^tiOnS
C»mwwou> ¦rtawNr
• Compan»on at catenated d«tary doset m
tjmrvDTOJi widlfe wHh TRV«
Note*
COPC • Clwncil d Potente* Concern
TRV« - Tcwaty r«rtnnw» va'ue*
Page 1 of 1
Section G Tabies-Eco-Q81507d.xls [G24 - Exposure Pathways]
-------
Table G-25
COC Concentrations Expected to Provide Adequate Protection of Ecological Receptors
Habitat
Type/Name
Exposure
Medium
COC
Protective
Level
Units
Basis
Assessment
End point
Upper Sutton Brook - Site
Channel
Sediment
1,2,4-Trimefhylbenzene
1.3
mg/kg
Site-Specific NOAEL
- Survival and growth of local
populations of benthic invertebrates
1,3,5-Trimethylbenzene
1.2
mg/kg
Site-Specific NOAEL
2-Methyf phenol
0.1
mg/kg
Site-Specific NOAEL
3-/4-Methylphenol
0.6
mg/kg
Site-Specific NOAEL
4-Methyl-2-pentanone
0.04
mg/kg
Site-Specific NOAEL
Acetone
0.07
mg/kg
Site-Specific NOAEL
Carbon Disulfide
0.001
mg/kg
Site-Specific NOAEL
Chloroethane
0.03
mg/kg
Site-Specific NOAEL
Ethylbenzene
0.09
mg/kg
Site-Specific NOAEL
Toluene
0.06
mg/kg
Site-Specific NOAEL
Xylenes (total)
0.13
mg/kg
Site-Specific NOAEL
Upper Sutton Brook - Site
Channel
Surface Water
4,4'-DDT
0.001
ug/L
NRWQC
• Survival and growth of potential fish
and invertebrate communities
Ethylbenzene
7.3
ug/L
Site-Specific NOAEL
T oluene
9.8
ug/L
Site-Specific NOAEL
Xylenes (total)
13
ug/L
Site-Specific NOAEL
Former Drum Disposal
Area
Soil
1,2,4-T rimethylbenzene
1.1
mg/kg
Site-Specific NOAEL
- Sustainability (survival, growth,
reproduction) of local populations of
carnivorous wMife (robin)
1,3,5-Trimethylbenzene
1.1
mg/kg
Site-Specific NOAEL
bis(2-Ethylhexyl)phthalate
2.3
mg/kg
HQ =0.1
Di-n-octylphthalate
0.1
mg/kg
X
o
II
p
- abundance and diversity of plants
Ethylbenzene
1.1
mg/kg
s
te-Specific NOAEL
Naphthalene
mg/kg
s
te-Specific NOAEL
Toluene
1.1
mg/kg
s
te-Specific NOAEL
Xylenes (total)
1.1
mg/kg
s
te-Specific NOAEL
Garage and Storage Area
Soil
Di-n-octylphthalate
0.4
mg/kg
HQ = 0.1
- Sustainability (suiwal, growth,
reproduction) of local populations of
carnivorous widEfe (robin)
- survival and growth of invertebrtates
Lead
65
mg/kg
d
1!
a
i
Zinc
190
mg/kg
Site-Specific LOAEL
Motes:
HQ - Hazard Quotient
NOAEL - No Observable Adverse Effect Level
COC * Chemical of Concern
LOAEL - Lowest Observable Adverse Effect Level
NRWQC - National Recommended Water Quality Criterion
Page 1 of 1
Section G Tables-Eco-081507d.xls [G25 - Eco PRGs]
-------
TABLE LF-1
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table LF-1: No Action
EVALUATION CRITERIA
DETAILED ANALYSIS
Type and Quantity of Residuals
Remaining after Treatment
Existing conditions will remain since no treatment is proposed.
Degree to Which Treatment
No treatment is proposed.
Reduces Principal Threats
SHORT-TERM EFFECTIVENESS
Protection of Community During
Remedial Action
Not applicable since no remedial actions are included in this alternative.
Protection of Workers During
Remedial Action
Not applicable since no remedial actions are included in this alternative.
Environmental Impacts
Not applicable since no remedial actions are included in this alternative.
No active remedial actions will be implemented to contain the landfill waste or to
Time Until Remedial Action
reduce concentrations in sediment, surface water or groundwater to cleanup goals.
Objectives are Achieved
Therefore, RAO's will not be achieved through this alternative in the foreseeable
future,
Ability to Construct and Operate
the Technology
Not applicable since no remedial actions are included in this alternative.
Reliability of the Technology
Not applicable since no remedial actions are included in this alternative.
Ease of Undertaking Additional
This alternative will not limit or interfere with the ability to implement or perform
Remedial Actions, if necessary
future remedial actions.
Ability to Monitor Effectiveness
Not applicable since no remedial actions or monitoring are included in this
of Remedy
alternative.
Ability to Obtain Approvals and
Not applicable since no remedial actions are included in this alternative; therefore,
Coordinate with Other Agencies
no approvals or coordination required.
Availability of off-site
Treatment, Storage and Disposal
Not applicable for this alternative.
Services and Capacity
Availability of Necessary
Equipment and Specialists
No equipment or specialists required for this alternative.
Availability of Technology
Not applicable since no remedial technologies will be used.
COSTS - net present value (7%) - 30 years
Capital Costs
$0
Annua] Operation, Maintenance
$68,000
and Monitoring
Periodic Costs
$43,000
TOTAL
$111,000
LF-1
-------
TABLE LF-2a
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table LF-2a: Containment of waste, vent landfill gas, restoration of wetlands and brook,
containment of groundwater with a vertical barrier and groundwater remediation
EVALUATION CRITERIA
DETAILED ANALYSIS
OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT ,
The HHRA presumed that the Northern and Southern landfill lobes will be capped;
thereby eliminating direct exposure to soils located in these areas. The results of the
HHRA concluded if groundwater is used as a source of potable water, groundwater may
also pose a risk to hypothetical future site residents or workers.
Human Health Protection
Under this alternative, the landfill waste will be capped and impacted groundwater
immediately downgradient of the Southern lobe will be prevented from discharging into
the brook {preventing migration and potential re-contamination of the brook), sediments
within the brook will be excavated, and in-situ natural attenuation mechanisms will be
monitored to address groundwater impacts. In conjunction with institutional controls,
future risk of groundwater ingestion by site users will be controlled, therefore the site
RAOs will be achieved.
Ecological Protection
The results of the ecological risk assessment indicated that VOCs and/or metals in
sediment and surface water within Sutlon Brook between the two landfill lobes may pose
a potential risk to ecological receptors. Due to these potential risks, PRGs were
established for the specific constituents determined to be "risk drivers" in sediment and
surface water.
Under this alternative, the landfill waste will be capped, the Southern lobe impacted
groundwater will be controlled, minimizing discharge to the brook (preventing potential
re-contamination of the brook sediment/surface water) and excavation of the impacted
sediment will be conducted to reduce concentrations to meet RAOs.
COMPLIANCE WITH ARARs
Chemical Specific
Potential chemical specific ARARs for this alternative are presented in Table E-l in
Appendix E; this alternative will be designed and implemented to comply with applicable
chemical-specific ARARs.
Location Specific
Potential location specific ARARs for this alternative are presented in Table E-l in
Appendix E; this alternative will be designed and implemented to comply with applicable
location-specific ARARs.
Action Specific
Action specific ARARs for this alternative are presented in Table E-l in Appendix E;
this alternative will be designed and implemented to comply with applicable action-
specific ARARs.
LONG-TERM EFFECTIVENESS AND PERMANENCE
With the construction of a final cover system over the landfill lobes and she excavation of
impacted sediment from the brook, the residual risks for direct exposure of landfill waste
and impacted sediment "are eliminated. However, given the potential for some wastes to
have been placed near or at the water table surface, the potential will remain for some
.. . . , leaching of contaminants from the waste into groundwater. Prevention of further impacts
Magnitude of Residual Risk , , , .
to the brook through groundwater containment and natural attenuation mechanisms will
minimize future residual risk to re-contaminating the brook sediment and/or surface
water. In conjunction with institutional controls, future risk of groundwater ingestion by
site users will be controlled. Therefore, residual risk is low for this alternative. I
LF-2a
-------
TABLE LF-2a
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table LF-2a: Containment of waste, vent landfill gas, restoration of wetlands and brook,
containment of groundwater with a vertical barrier and groundwater remediation
EVALUATION CRITERIA
DETAILED ANALYSIS
Adequacy and Reliability of
Controls
Capping of the landfill waste is an effective and reliable technology to prevent exposure
lo the waste and to reduce infiltration through the waste and leaching to groundwater.
The combination of groundwater containment (via a vertical barrier), natural attenuation
mechanisms, and institutional controls will effectively and reliably limit human exposure
to impacted groundwater until groundwater RAOs are met. Monitoring of the
containment system and natural attenuation mechanisms will be required to demonstrate
reliability.
REDUCTION OF TOXICITY, MOBILITY AND VOLUME THROUGH TREATMENT
Treatment Process Used and
Materials Treated
This alternative does not treat the landfill waste. Treatment of the excavated sediment is
not anticipated prior to on-site disposal beneath the landfill final cover system; however,
if deemed necessary based on the pre-design waste characterization results of the
material being excavated, ex-situ treatment of soil may be implemented prior to on-site
disposal. This alternative does not actively treat groundwater, Monitored natural
attenuation processes will address COCs in situ. Following the phased approach, this
alternative may also include an active groundwater treatment component.
Amount Destroyed or Treated
The landfill waste and excavated sediment are not anticipated to be treated.
Groundwater will be addressed with natural attenuation processes. Current dissolved
concentrations indicate an estimated 2,700 to 4,500 lbs of VOCs in Northern and
Southern lobe groundwater.
Degree of Expected Reductions
in Toxicity, Mobility or Volume
through Treatment
Compared to the other alternatives evaluated for the landfill lobes, this alternative
provides a low level of reduction in toxicity, mobility and volume of contaminants
through treatment.
Degree to which Treatment is
Irreversible
This alternative does not include active treatment technologies.
This alternative does not treat the landfill waste. Through excavation of the impacted
Type and Quantity of Residuals sedimem» no residuals presenting exposure risks will remain. This alternative does not
Remaining after Treatment
actively treat groundwater. Monitored natural attenuation processes will address COCs in
situ.
Degree to Which Treatment
Reduces Principal Threats
Principal threats of direct exposure and potential leaching from waste to groundwater are
addressed via landfill containment (cap). The principal threats/ exposure risks of
groundwater migration and ingestion will be controllecVredueed through groundwater
containment (via vertical barrier), natural attenuation, and institutional controls.
LF-2a
-------
TABLE LF-2a
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table LF-2a: Containment of waste, vent landfill gas, restoration of wetlands and brook,
containment of groundwater with a vertical barrier and groundwater remediation
EVALUATION CRITERIA
DETAILED ANALYSIS
SHORT-TERM EFFECTIVENESS -
Protection of Community During
Remedial Action
This alternative will have moderate short-term effects on the local community during the
construction of the landfill final cover system due to an increase in local truck/ vehicular
traffic (bringing in soil cover material). Limited short term effects are anticipated as a
result of the sediment excavation or groundwater MNA portions of this alternative.
Protection of Workers During
Remedial Action
Work will he performed in accordance with applicable OSHA standards. Site-specific
health and safety plan{s) will be developed to protect site workers.
Environmental Impacts
Impacts to the wetland resource areas are anticipated to be low to moderate during
construction activities due to the location of the wetland resource areas surrounding the
landfill lobes (erosion controls and stormwater management will be required to reduce
impacts) and during the brook excavation, temporary re-directing/routing of the brook
may be required to effectively remove the impacted sediment, potentially causing
disruption to the existing ecological habitat. Once the landfill capping and brook
excavation are complete and the area restored, operation and monitoring activities are
anticipated to have minimal impacts. Available practical means such as erosion and
stormwater control measures will also be implemented to minimize harm to wetland areas
during construction.
Time Until Remedial Action
Objectives are Achieved
Landfill waste RAOs will be achieved upon construction of the final cover system
(design/approvals 1 year, construction 2 to 3 years) and the sediment RAOs will be
achieved upon removal of the impacted sediment (confirmatory sediment sampling will
be performed to document the achievement of RAOs) - (design/approvals - 1 year,
construction/restoration 1 to 1.5 years).
The estimated time to achieve groundwater RAOs is approximately
65 to 210 years
IMPLEMENTABILITY
Construction of the landfill final cover system is a common technique that is straight
forward to implement; the presence of wetland resource areas and the adjacent i00-year
flood plain may present potential design challenges (stormwater management, etc.).
Preliminary evaluation of stormwater/ drainage features at the site indicate that upon
capping the landfill, use of the FDDA and Deep Marsh may be required for stormwater
Ability to Construct and Operate detention ponds. Excavation of impacted sediment from existing waterways is a fairly
the Technology common construction activity; site specific engineering and erosion controls will be
required to minimize environmental impacts. The installation of a vertical containment
barrier involves common construction techniques. This alternative requires a lower level
of operation, maintenance, and monitoring than other alternatives evaluated (e.g. LF-3).
Reliability of the Technology
Excavation of impacted sediment is an effective and reliable method since the material
will be removed. Capping of the landfill waste is an effective and reliable technology to
prevent direct exposure to the waste and to reduce infiltration through the waste into
groundwater. The combination of groundwater containment (via a vertical barrier),
natural attenuation, and institutional controls should effectively and reliably limit human
exposure to impacted groundwater until groundwater RAOs are met.
LF-2a
-------
TABLE LF-2a
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table LF-2a: Containment of waste, vent landfill gas, restoration of wetlands and brook,
containment of groundwater with a vertical barrier and groundwater remediation
EVALUATION CRITERIA
DETAILED ANALYSIS
Ease of Undertaking Additional
This alternative should not limit or interfere with the ability lo implement or perform
future remedial actions.
Remedial Actions, if necessary
Confirmatory sediment sampling and analysis is easily implemciUable to measure the
Ability to Monitor Effectiveness
effectiveness of the brook sediment excavation. Groundwater monitoring to demonstrate
of Remedy
contaminant containment and mass reduction is easily implemcntable.
Ability to Obtain Approvals and
Coordinate with Other Agencies
The remedial action will be designed and implemented under coordination with
appropriate Federal and State agencies.
Facilities are available to treat or dispose of the excavated sediment within
Availability of off-site
Treatment, Slorage and Disposal
Massachusetts. However, there is also availability to re-use this material on-site at one of
the landfill lobes beneath the final cover system.
Services and Capacity
Availability of Necessary
Equipment, materials and services for this alternative are readily available.
Equipment and Specialists
Availability of Technology
Qualified engineers and contractors are available to design and implement this
alternative.
COSTS * net present value (7%) - 30 yearn
¦ ¦ LF-2a
Capital Costs
$17,500,000
Annua! Operation, Maintenance
and Monitoring
$2,900,000
Periodic Costs
$120,000
TOTAL
$20,520,000
LF-2a
-------
TABLE LF-2b
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table LF-2b: Containment of waste, vent landfill gas, restoration of wetlands and brook,
containment of groundwater with a vertical barrier and groundwater remediation
EVALUATION CRITERIA
DETAILED ANALYSIS
OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT
The HHRA presumed that the .Northern and Southern landfill lobes will be capped;
thereby eliminating direct exposure to soils located in these areas. The results of the
HHRA concluded if groundwater is used as a source of potable water, groundwater may
also pose a risk to hypothetical future site residents or workers.
Human Health Protection
Under this alternative, the landfill waste will be capped, sediments within the brook will
be excavated, impacted groundwater immediately downgradient of the Southern lobe
will be treated and prevented from discharging into the brook (preventing migration and
potential re-contamination of the brook) and impacted groundwater from the Northern
lobe will be addressed by in-situ natural attenuation. In conjunction with institutional
controls, future risk of groundwater ingestion by site users will be controlled, therefore
the site RAOs will be achieved.
Ecological Protection
The results of the ecological risk assessment indicated that VOCs and/or metals in
sediment and surface water within Sutton Brook between the two landfill lobes may pose
a potential risk to ecological receptors. Due to these potential risks, PRCs were
established for the specific constituents determined to be "risk drivers" in sediment and
surface water.
Under this alternative, the landfill waste will be capped, the Southern lobe impacted
groundwater will be controlled, minimizing discharge to the brook (preventing potential
re-contamination of the brook sediment/surface water) and excavation of the impacted
sediment will be conducted to reduce concentrations to meet RAOs.
COMPLIANCE WITH ARARs
Chemical Specific
Potential chemical specific ARARs for this alternative are presented in Table L: 1 in
Appendix E; this alternative will be designed and implemented to comply with applicable
chemical-specific ARARs.
Location Specific
Potential location specific ARARs for this alternative are presented in Table E-l in
Appendix E; this alternative will be designed and implemented to comply with applicable
location-specific ARARs.
Action Specific
Action specific ARARs for this alternative are presented in Table E-l in Appendix E;
this alternative will be designed and implemented to comply with applicable action-
specific ARARs.
LONG-TERM EFFECTIVENESS AND PERMANENCE
Magnitude of Residual Risk
With the construction of a final cover system over the landfill lobes and the excavation of
impacted sediment from the brook, the residual risks for direct exposure of landfill waste
and impacted sediment are eliminated. However, given the potential for some wastes to
have been placed near or at the water table surface, the potential will remain for some
leaching of contaminants from the waste into groundwater. Prevention of further impacts
to the brook through groundwater containment and focused groundwater remediation will
minimize future residual risk to re-contaminating the brook sediment and/or surface
water. In conjunction with institutional controls, future risk of groundwater ingestion by
site users will be controlled- Therefore, residual risk is low for this alternative.
LF-2b
-------
TABLE LF-2b
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table LF-2b: Containment of waste, vent landfill gas, restoration of wetlands and brook,
containment of groundwater with a vertical barrier and groundwater remediation
EVALUATION CRITERIA
DETAILED ANALYSIS
Adequacy and Reliability of
Controls
Capping of the landfill waste is an effective and reliable technology to prevent exposure
to the waste and to reduce infiltration through the waste and leaching to groundwater.
The combination of groundwater containment (via a vertical barrier), focused
groundwater remediation and institutional controls will effectively and reliably limit
human exposure to impacted groundwater until groundwater RAOs are met. Monitoring
of the containment system and focused groundwater remediation will be required to
demonstrate reliability.
REDUCTION OF TOXICITY, MOBILITY. AND VOLUME THROUGH TREATMENT
Treatment Process Used and
Materials Treated
This alternative does not treat the landfill waste. Treatment of the excavated sediment is
not anticipated prior to on-site disposal beneath the landfill final cover system; however,
if deemed necessary based on the pre-design waste characterization results of the
materia! being excavated, ex-situ treatment of soil may be implemented prior to on-site
disposal.
Materials addressed in groundwater through focused groundwater remediation (in situ or
ex situ) will include VQCs, SVOCs & metals; If extraction and ex-situ treatment of
groundwater are implemented, a combination of technologies such as air stripping,
advanced oxidation processes and/or metals treatment, in addition to one or more
prctrcatment steps (to be determined during the design phase) will be utilized to treat the
extracted groundwater.
Amount Destroyed or Treated
The landfill waste and excavated sediment are not anticipated to be treated.
Groundwater will be remediated with in situ treatment enhancements/technologies and/or
groundwater ex-situ treatment. Current dissolved concentrations indicate an estimated
2,700 to 4,500 lbs of VOCs in Northern and Southern lobe groundwater.
Degree of Expected Reductions
in Toxicity, Mobility or Volume
through Treatment
Compared to the other alternatives evaluated for the landfill lobes, this alternative
provides a moderate level of reduction in toxicity, mobility and volume of contaminants
through groundwater treatment.
Degree lo which Treatment is
Irreversible
The groundwater treatment/remediation will be permanent.
Type and Quantity of Residuals
Remaining after Treatment
This alternative does not treat the landfill waste. Through excavation of the impacted
sediment, no residuals presenting exposure risks will remain. In situ and/or ex-situ
groundwater treatment and any resulting VOC vapors or end-products may produce a low
volume of treatment residuals that will require off-site treatment/disposal at a licensed
facility.
Degree to Which Treatment
Reduces Principal Threats
Principal threats of direct exposure and potential leaching from waste to groundwater are
addressed via landfill containment (cap). The principal threats/ exposure risks of
groundwater migration and ingestion will be controlled through groundwater containment
(via vertical barrier), groundwater treatment (in situ or ex situ), natural attenuation, and
institutional controls.
LF-2b
-------
TABLE LF-2b
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table LF-2b: Containment of waste, vent landfill gas, restoration of wetlands and brook,
containment of groundwater with a vertical barrier and groundwater remediation
EVALUATION CRITERIA
DETAILED ANALYSIS
SHORT-TERM EFFECTIVENESS
This alternative will have moderate short-term effects on the local community during the
construction of the landfill final cover system due to an increase in local truck/ vehicular
Protection of Community During tranlc (bringing in soil cover material). Limited short term effects are anticipated as a
Remedial Action result of the sediment excavation or groundwater containment/remediation portions of
this alternative.
Protection of Workers During Work will be performed in accordance with applicable OSHA standards. Site-specific
Remedial Action health and safety plan{s) will be developed to protect site workers.
Environmental Impacts
Impacts to the wetland resource areas are anticipated to he low to moderate during
construction activities due to the location of the wetland resource areas surrounding the
landfill lobes (erosion controls and stormwater management will be required to reduce
impacts) and during the brook excavation, temporary re-directing/routing of the brook
may be required to effectively remove the impacted sediment, potentially causing
disruption to the existing ecological habitat. Once the landfill capping and brook
excavation are complete, the groundwater containment/remediation components installed,
and the area restored, operation and monitoring activities are anticipated to have minimal
impacts. Available practical means such as erosion and stormwater control measures will
also he implemented to minimize harm to wetland areas during construction.
Time Until Remedial Action
Objectives are Achieved
Landfill waste RAOs will be achieved upon construction of the final cover system
(design/approvals 1 year, construction 2 to 3 years) and the sediment RAOs will be
achieved upon removal of the impacted sediment (confirmatory sediment sampling will
be performed to document the achievement of RAOs) - (design/approvals - I year,
construction/restoration I to 1.5 years),
The estimated time to achieve groundwater RAOs is approximately
65 to 210 years
1MPLEMENITABILITY
Construction of the landfill final cover system is a common technique that is straight
forward to implement; the presence of wetland resource areas and the adjacent 100-year
flood plain may present potential design challenges (stormwater management, etc.).
Preliminary evaluation of stormwater/ drainage features at the site indicate that upon
capping the landfill, use of the FDDA and Deep Marsh may be required for stormwater
Ability to Construct and Operate detention ponds. Excavation of impacted sediment from existing waterways is a fairly
the Technology common construction activity; site specific engineering and erosion controls will be
required to minimize environmental impacts. The installation of a vertical containment
barrier and implementation of the focused groundwater remediation program involves
common construction techniques. This alternative requires a lower level of operation,
maintenance, and monitoring than other alternatives evaluated (e.g. LF-3).
Reliability of the Technology
Excavation of impacted sediment is an effective and reliable method since the material
will be removed. Capping of the landfill waste is an effective and reliable technology to
prevent direct exposure to the waste and to reduce infiltration through the waste into
groundwater. The combination of groundwater containment (via a vertical barrier),
focused groundwater remediation and institutional controls should effectively and
reliably limit human exposure to impacted groundwater until groundwater RAOs are met.
LF-2b
-------
TABLE LF-2b
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table LF-2b: Containment of waste, vent landfill gas, restoration of wetlands and brook,
containment of groundwater with a vertical barrier and groundwater remediation
EVALUATION CRITERIA
DETAILED ANALYSIS
Ease of Undertaking Additional
Remedial Actions, if necessary
This alternative should not limit or interfere with the ability to implement or perform
future remedial actions.
Ability to Monitor Effeeliveness
of Remedy
Confirmatory sediment sampling and analysis is easily implementable to measure the
effectiveness of the brook sediment excavation. Groundwater monitoring to demonstrate
contaminant containment and mass reduction is easily implementable.
Ability to Obtain Approvals and
Coordinate with Other Agencies
The remedial action will be designed and implemented under coordination with
appropriate Federal and State agencies.
Availability of off-site
Treatment, Storage and Disposal
Services and Capacity
Facilities are available to treat or dispose of the excavated sediment within
Massachusetts. However, there is also availability to re-use this material on-site at one of
the landfill lobes beneath the final cover system. If groundwater extraction and cx-situ
treatment are implemented, the treated groundwater can be discharged to surface water or
to the local POTW.
Availability of Necessary
Equipment and Specialists
Equipment, materials and services for this alternative are readily available.
Availability of Technology
Qualified engineers and contractors are available to design and implement this
alternative.
COSTS - net present value (7%) - 30 years
LF-2b
Capital Costs
$19,700,000
Annual Operation, Maintenance
and Monitoring
$5,400,000
Periodic Costs
$120,000
TOTAL
$25,220,000
LF-2b
-------
TABLE LF-3
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table LF-3: Containment of waste, vent landfill gas, restoration of wetlands and brook and
contaminated groundwater collection and treatment
EVALUATION CRITERIA
DETAILED ANALYSIS
OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT
Human Health Protection
The HHRA presumed that the Northern and Southern landfill lobes will be capped; thereby
eliminating direct exposure to soils located in these areas. The results of the HHRA concluded if
groundwater is used as a source of potable water, groundwater may also pose a risk to
hypothetical future site residents or workers.
Under this alternative, the landfill waste will he capped and impacted groundwater will be
hydraulically controlled and treated (preventing migration and potential re-contamination of the
brook), therefore the potential human health risks will be eliminated and RAOs will be achieved.
Ecological Protection
The results of the ecological risk assessment indicated that VOCs and/or metals in sediment and
surface water within Sutton Brook between the two landfill lobes may pose potential risk to
ecological receptors. Due to these potential future risks, PRCs were established for the specific
constituents determined to the "risk drivers" in sediment and surface water.
Under this alternative, the landfill waste will be capped, the southern lobe impacted groundwater
will be hydraulically contained (preventing potential re-contamination of the brook
sediment/surface water) and excavation of the impacted sediment will be conducted to reduce
concentrations to meet RAOs.
COMPLIANCE WITH ARARs
Chemical Specific
Potential chemical specific ARARs for this alternative are presented in Table E-l in Appendix E;
this alternative will be designed and implemented to comply with applicable chemical-specific
ARARs.
Location Specific
Potential location specific ARARs for this alternative are presented in Table E-I in Appendix E;
this alternative will be designed and implemented to comply with applicable location-specific
ARARs.
Action Specific
Action specific ARARs for this alternative are presented in Table E-I in Appendix E; this
alternative will be designed and implemented to comply with applicable action-specific ARARs.
LONG-TERM EFFECTIVENESS AND PERMANENCE
Magnitude of Residual Risk
With the construction of a final cover system over the landfill lobes and the excavation of
impacted sediment from the brook, the residual risks for direct exposure of landfill waste and
impacted sediment are eliminated. However, given the potential for some wastes to have been
placed near or at the water table surface, the potential will remain for some leaching of
contaminants from the waste into groundwater. Prevention of further impacts to the brook through
groundwater extraction and ex-situ treatment will minimize future residual risk to re-
contaminating the brook sediment and/or surface water. In conjunction with institutional controls,
future risk of groundwater ingestion by site users will be controlled. Therefore, residual risk is low
for this alternative,
Adequacy and Reliability of
Controls
Capping of the landfill waste is an effective and reliable technology to prevent direct exposure to
the waste and to reduce infiltration through the waste and leaching to groundwater. The
combination of groundwater hydraulic containment through groundwater extraction and ex-situ
treatment and institutional controls will effectively and reliably limit human exposure to impacted
groundwater until groundwater RAOs are met.
LF-3
-------
TABLE LF-3
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table LF-3: Containment of waste, vent landfill gas, restoration of wetlands and brook and
contaminated groundwater collection and treatment
EVALUATION CRITERIA
DETAILED ANALYSIS
REDUCTION OF TOXICITY, MOBILITY AND VOLUME THROUGH TREATMENT
Treatment Process Used and
Materials Treated
This alternative docs not treat the landfill waste. Treatment of the.excavated sediment is not
anticipated prior to on-site disposal beneath the landfill final cover system; however, if deemed
necessary based on the pre-design waste characterization results of the material being excavated,
ex-situ treatment of soil may he implemented prior to on-site disposal.
Materials treated in groundwater through ex-situ groundwater treatment will include VOCs,
SVOCs & metals; a combination of technologies such as air stripping, advanced oxidation
processes and/or metals treatment, in addition to one or more pretreatment steps (to be determined
during the design phase) may be utilized to treat the extracted groundwater.
Amouni Destroyed or Treated
The landfill waste and excavated sediment are not anticipated to be treated. Groundwater will be
treated/destroyed with ex-situ treatment processes. Current dissolved concentrations indicate an
estimated 2,700 to 4,500 lbs of VOCs in Northern and Southern lobe groundwater available for
treatment.
Degree of Expected Reductions
in Toxicity, Mobility or Volume
through Treatment
Compared to other alternatives evaluated for the landfill lobes, this alternative provides a
moderate level of reduction in toxicity, and volume and a high level of reduction in mobility of
dissolved contaminants through groundwater extraction and treatment.
Degree to which Treatment is
Irreversible
The groundwater treatment will be permanent.
Type and Quantity of Residuals
Remaining after Treatment
This alternative does not treat the landfill waste. Through excavation of the impacted sediment,
no residuals presenting exposure risks will remain. Treatment of the groundwater plume and any
resulting VOC vapors will produce a moderate to high volume of treatment residuals that will
require off-site treatment/disposal at a licensed facility.
Degree to Which Treatment
Reduces Principal Threats
Principal threats of direct exposure and potential leaching from waste to groundwater are not
addressed via treatment for this alternative (containment and excavation); however, through
groundwater extraction and ex-situ treatment, and institutional controls, the principal threats/
exposure risks of groundwater migration and ingestion will be reduced.
SHORT-TERM EFFECTIVENESS .
This alternative will have moderate short-ierm effects on the local community during the
Protection of Community During construction of the landfill final cover system due to an increase in local truck/ vehicular traffic
Remedial Action {bringing in soil cover material). Limited short term effects are anticipated as a result of the
sediment excavation or groundwater treatment system installation portions of this alternative.
Protection of Workers During
Remedial Action
Work will be performed in accordance with applicable OSHA standards. Site-specific health and
safety plan(s) will be developed to protect site workers.
Environmental Impacts
Impacts to the wetland resource areas arc anticipated to be moderate during construction activities
due to the location of the wetland resource areas surrounding the landfill lobes (erosion controls
and stormwater management will be required to reduce impacts) and during the brook excavation,
temporary re-directing/routing of the brook may be required to effectively remove the impacted
sediment, potentially causing disruption to the existing ecological habitat. Once the landfill
capping and brook excavation are complete, the groundwater hydraulic containment/ ex-situ
treatment system installed, and the area restored, operation and monitoring activities are
anticipated to have minimal environmental impacts. Available practical means such as erosion
and stormwater control measures will also be implemented to minimize harm to wetland areas
during construction.
LF-3
-------
TABLE LF-3
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table LF-3: Containment of waste, vent landfill gas, restoration of wetlands and brook and
contaminated groundwater collection and treatment
EVALUATION CRITERIA
DETAILED ANALYSIS
Time Unlil Remedial Action
Objectives are Achieved
Landfill waste RAOs will be achieved upon construction of the final cover system
(design/approvals 1 year, construction 2 to 3 years) and the sediment RAOs will be achieved upon
removal of the impacted sediment (confirmatory sediment sampling will be performed to
document the achievement of RAOs) - (design/approvals - 1 year, construction/restoration 1 to 1,5
years).
The estimated lime to achieve groundwater RAOs is approximately
52 to 164 years
IMPLEMENTABILITY
Construction of a landfill final cover system is a common technique that is straight forward to
implement; the presence of wetland resource areas and the adjacent 100-year flood plain may
present potential design challenges {stormwater management, etc.). Preliminary evaluation of
stormwater/ drainage features at the site indicate that upon capping the landfill, use of the FDDA
Ability to Construct and Operate and Deep Marsh will likely be required for stormwater detention ponds. Excavation of impacted
the Technology sediment from existing waterways is a fairly common construction activity; site specific
engineering and erosion controls will be required to minimize environmental impacts. The
installation of a groundwater treatment system involves common construction techniques. This
alternative requires a higher level of operation, maintenance and monitoring compared to other
alternatives evaluated (e.g. LF-2 and LF-4).
Reliability of the Technology
Excavation of impacted sediment is an effective and reliable method since the material will be
removed. Capping of the landfill waste is an effective and reliable technology to prevent direct
exposure to the waste and to reduce infiltration through the waste into groundwater. The
combination of groundwater treatment and institutional controls should limit human exposure to
impacted groundwater until groundwater RAOs arc met. This alternative, however, has a reduced
level of reliability in containing the groundwater in comparison to alternative LF-2 due to the
potential for mechanical failure of Equipment over time, providing the potential for groundwater to
migrate into the brook and/or downgradient.
Ease of Undertaking Additional
Remedial Actions, if necessary
This alternative should not limit or interfere with the ability to implement or perform future
remedial actions.
Ability to Monitor Effectiveness
of Remedy
Confirmatory sediment sampling and analysis is easily implcmentable to measure the effectiveness
of the brook sediment excavation. Groundwater monitoring to demonstrate contaminant
containment and reduction is easily implementable.
Ability to Obtain Approvals and
Coordinate with Other Agencies
The remedial action will be designed and implemented under coordination with appropriate
Federal and State agencies.
Availability of off-site
Treatment, Storage and Disposal
Services and Capacity
Facilities are available to treat or dispose of the excavated sediment within Massachusetts.
However, there is also availability to re-use this material on-site at one of the landfill lobes
beneath the final cover system. Treated groundwater can be discharged to surface water or to the
local POTW.
Availability of Necessary
Equipment and Specialists
Equipment, materials and services for this alternative are readily available.
Availability of Technology
Qualified engineers and contractors are available to design and implement this alternative.
COSTS - net present value (7%) - 30 years
Capital Costs
$24,900,000
Annual Operation, Maintenance
and Monitoring
$ 15,900,000 to $26,100,000
Periodic Costs
$130,000
TOTAL
$40,930,000 to $51,130,000
LF-3 - O&M Range incorporates: 30 years of system operation with 30 years of groundwater monitoring -low: discharge to surface water, high:
discharge to POTW
LF-3
-------
TABLE LF-4
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table LF-4; Containment of waste, vent landfill gas, re-routing of the brook,
excavation of impacted sediment hot spots, containment of groundwater (vertical
EVALUATION CRITERIA
DETAILED ANALYSIS
OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT
Human Health Protection
The lilIRA presumed that the Northern and Southern landfill lobes will be
capped; thereby eliminating direct exposure to soils located in these areas. The
results of the HHRA concluded if groundwater is used as a source of potable
water, groundwater may also pose a risk to hypothetical future site residents or
workers.
Under this alternative, the landfill waste will be capped and impacted
groundwater immediately adjacent to the Southern lobe will be remediated and
prevented from discharging into the brook (preventing migration and potential
re-contamination of the brook) and impacted groundwater from the Northern
lobe will be addressed by in-situ natural attenuation, therefore the potential
human health risks will be controlled and RAOs will be achieved.
Ecological Protection
The results of the ecological risk assessment indicated that VOCs and/or metals
in sediment and surface water within Sutton Brook between the two landfill
lobes may pose potential risk to ecological receptors. Due to these potential
risks, PRGs were established for the specific constituents determined to be "risk
drivers" in sediment and surface water.
Under this alternative, the landfill waste will be capped, hot spot areas within
the brook will be excavated, the brook will be re-routed around the Southern
Lobe, and impacted groundwater from the Southern lobe will be
controlled/treated, minimizing discharge to the newly re-routed brook.
Through these remedial actions, RAOs will be achieved.
COMPLIANCE WITH ARARs
Chemical Specific
Chemical specific ARARs for this alternative are presented in Table E-l in
Appendix E; this alternative will be designed and implemented to comply with
applicable chemical specific ARARs.
Location Specific
Potential location specific ARARs for this alternative are presented in Table E-
1 in Appendix E. Resource areas which will require alteration include
Bordering Land Subject to Flooding, Inland Bank, Land Under Water,
Riverfront Area, and Bordering Vegetated Wetlands. Due to the issues involved
with re-routing the brook (with respect to altering and re-creating these
resource areas and re-creating the 100-year flood plain), specifically the lack of
space available to fully mitigate {both the function and value) of the loss of
resource areas, in conjunction with a major disruption to the existing
hydrogeological features and ecological habitats, this alternative will most
likely not meet applicable location-specific ARARs.
Action Specific
Action specific ARARs for this alternative are presented in Table E-l in
Appendix E; this alternative will be designed and implemented to comply with
applicable action-specific ARARs.
LF-4
-------
TABLE LF-4
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table LF-4: Containment of waste, vent landfill gas, re-routing of the brook,
excavation of impacted sediment hot spots, containment of groundwater (vertical
EVALUATION CRITERIA
DETAILED ANALYSIS
LONG-TERM EFFECTIVENESS AND PERMANENCE
Magnitude of Residual Risk
With the construction of a final cover system over the landfill lobes, the
excavation of hot spot areas of impacted sediment from the former brook and
' the re-creation of the brook around the southern edge of the landfill, the
residual risks for direct exposure of landfill waste and impacted sediment are
reduced. Further impacts to the newly re-routed brook through groundwater
containment (vertical barrier) and focused groundwater treatment will reduce
future residual risk to contaminating the re-routed brook sediment and/or
surface water and, in conjunction with institutional controls, will control future
risk of groundwater ingestion by future site users. Therefore, residual risk is
low for this alternative.
Adequacy and Reliability of
Controls
Capping of the landfill waste is an effective and reliable technology to prevent
exposure to the waste and to reduce infiltration through the waste leaching to
groundwater. Re-routing of the brook around the Southern lobe, in conjunction
with (he vertical groundwater containment barrier, will effectively and reliably
minimize future contamination of the brook sediment and/or surface water.
The combination of groundwater containment (via a vertical barrier), focused
groundwater treatment and institutional controls should effectively and reliably
limit human exposure to impacted groundwater until groundwater RAOs are
achieved. Monitoring of the containment system and focused groundwater
treatment will be required to demonstrate reliability.
REDUCTION OF TOXICITY, MOBILITY AND VOLUME THROUGH TREATMENT
Treatment Process Used and
Materials Treated
This alternative does not treat the landfill waste. Treatment of the excavated
sediment is not anticipated prior to on-site disposal beneath the landfill final
cover system; however, if deemed necessary based on the pre-design waste
characterization results of the material being excavated, ex-situ treatment of
soil may be implemented prior to on-site disposal.
Materials treated in groundwater through focused groundwater treatment will
include VOCs, SVOCs & metals; in situ measures could actively treat these
COCs and if extraction and ex-situ treatment of groundwater are implemented,
a combination of technologies such as air stripping, advanced oxidation
processes and/or metals treatment, in addition to one or more pretreatment steps
(to be determined during the design phase) will be utilized to treat the extracted
groundwater.
Amount Destroyed or Treated
The landfill waste and excavated sediment are not anticipated to be treated.
Groundwater will be treated/destroyed by in situ measures and/or groundwater
ex situ treatment. Current dissolved concentrations indicate an estimated 2,700
to 4,500 lbs of VOCs in Northern and Southern lobe groundwater.
LF-4
-------
TABLE LF-4
DETAILED analysis of remedial alternative
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table LF-4: Containment of waste, vent landfill gas, re-routing of the brook,
excavation of impacted sediment hot spots, containment of groundwater (vertical
EVALUATION CRITERIA
DETAILED ANALYSIS
Degree of Expected Reductions
in Toxicity, Mobility or Volume
through Treatment
Compared to the other alternatives evaluated for the landfill lobes, this
alternative provides a moderate level of reduction in toxicity, mobility and
volume of contaminants through groundwater treatment.
Degree to which Treatment is
Irreversible
The groundwater treatment will be permanent.
Type and Quantity of Residuals
Remaining after Treatment
This alternative does not treat the landfill waste. Through excavation of" the
impacted sediment, no residuals presenting exposure risks will remain. If
groundwater extraction and ex-situ treatment is implemented, treatment of
groundwater and any resulting VGC vapors will produce a low volume of
treatment residuals that will require off-site treatment/disposal at a licensed
facility.
Degree to Which Treatment
Reduces Principal Threats
Principal threats of direct exposure and potential leaching from waste to
groundwater are addressed via landfill containment (cap). The principal
threats/ exposure risks of groundwater migration and ingestion will be
controlled through groundwater containment (via vertical barrier), groundwater
treatment, natural attenuation, and institutional controls.
SHORT-TERM EFFECTIVENESS
Protection of Community During This alternative will have moderate to high short-term effects on the local
Remedial Action community during the construction of the landfill final cover system and the re-
routing of the brook due to an increase in local truck/ vehicular traffic (bringing
in soil cover material, lengthier construction timeframe). Limited short term
effects are anticipated as a result of the groundwater containment/treatment
portions of this alternative.
Protection of Workers During
Remedial Action
Work will be performed in accordance with applicable OS HA standards. Site-
specific health and safety plan(s) will be developed to protect site workers.
Environmental Impacts
Impacts to the wetland resource areas are anticipated to be high during
construction activities due to the destruction of the existing wetland/marsh area
to the south of the Southern lobe during the brook re-creation (disrupting
ecological habitat) and due to the location of the wetland resource areas
surrounding the landfill lobes (erosion controls and stormwater management
will be required to reduce impacts). Once the landfill capping, brook re-
creation, former brook excavation and filling are complete, the groundwater
containment/treatment components installed, and the area restored,
groundwater operation and monitoring activities are anticipated to have limited
impacts.
LF-4
-------
TABLE LF-4
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table LF-4: Containment of waste, vent landfill gas, re-routing of the brook,
excavation of impacted sediment hot spots, containment of groundwater (vertical
EVALUATION CRITERIA
DETAILED ANALYSIS
Time Until Remedial Action
Objectives are Achieved
Landfill waste RAOs will be achieved upon construction of the final cover
system (design/ approval 1 year, construction 2 to 3 years) and the sediment
RAOs will be achieved upon re-routing of the brook, removal of the impacted
sediment and restoration of the former brook area - (design/ approvals 2 years,
construction/restoration 1 to 2 years).
The estimated time to achieve groundwater RAOs is approximately
65 to 210 years
IMPLEMENTABILITY ; ' - '.••--k:
Ability to Construct and Operate Construction of a landfill final cover system is a common technique that is
the Technology straight forward to implement; the presence of wetland resource areas and the
adjacent 100-year flood plain may present potential design challenges for the
cover system (stormwater management, etc.). Preliminary evaluation of
stormwater/ drainage features at the site indicate that upon capping the landfill,
use of the FDDA and Deep Marsh may be required for stormwater detention
ponds.
Excavation of impacted sediment from existing waterways is a fairly common
construction activity; site specific engineering and erosion controls will be
required to minimize environmental impacts. Resource areas which will
require alteration with re-routing the brook include Bordering Land Subject to
Flooding, Inland Bank, Land Under Water, Riverfront Area, and Bordering
Vegetated Wetlands. Therefore, all work performed in these areas will present
numerous challenges with access and disruption.
The installation of a vertical containment barrier and implementation of the
focused groundwater treatment involves common construction techniques.
Reliability of the Technology
In conjunction with groundwater containment and treatment, re-routing of the
brook and excavation of hot-spot impacted sediment are effective and reliable
to eliminate current and potential future risks. Capping of the landfill waste is
an effective and reliable technology to prevent direct exposure to the waste and
to reduce infiltration through the waste into groundwater. The combination of
groundwater containment (via a vertical barrier), focused groundwater
treatment and institutional controls should effectively and reliably limit human
exposure to impacted groundwater until groundwater RAOs are met.
Ease of Undertaking Additional
Remedial Actions, if necessary
This alternative should not limit or interfere with the ability to implement or
perform future remedial actions.
Ability to Monitor Effectiveness
of Remedy
Confirmatory sediment sampling and analysis is easily implementable to
measure the effectiveness of the brook sediment excavation. Groundwater
monitoring to demonstrate contaminant containment and mass reduction is
easily implementable.
LF-4
-------
TABLE LF-4
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table LF-4: Containment of waste, vent landfill gas, re-routing of the brook,
excavation of impacted sediment hot spots, containment of groundwater (vertical
EVALUATION CRITERIA
DETAILED ANALYSIS
Ability to Obtain Approvals and
Coordinate with Other Agencies
With the potential ARAR issues in regards to the Wetlands Protection Act, this
alternative may have difficulty obtaining substantial compliance with federal
and state agencies.
Availability of off-site
Treatment, Storage and Disposal
Services and Capacity
Facilities are available to treat or dispose of the excavated sediment within
Massachusetts, However, there is also availability to re-use this material on-
site at one of the landfill lobes beneath the final cover system. If groundwater
extraction and ex-situ treatment are implemented, the treated groundwater can
be discharged to surface water or to the local POTW.
Availability of Necessary
Equipment and Specialists
Equipment, materials and services for this alternative are available.
Availability of Technology
Qualified engineers and contractors are available to design and implement this
alternative.
COSTS - net present value (7%) - 30 years
Capital Costs
$25,900,000
Annual Operation, Maintenance
and Monitoring
$5,400,000
Periodic Costs
$120,000
TOTAL
$31,420,000
LF-4
-------
TABLE FDDA-1
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table FDDA-1; No Action
EVALUATION CRITERIA
DETAILED ANALYSIS
OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT
The results of the human health risk assessment indicated that VOCs and SVOCs in
soil may pose a potential risk to receptors. The potential for volatilization of select
VOCs in groundwater may pose a potential risk to future site residents or facility
workers. If groundwater is used as a source of potable water, groundwater in the
Human Health Protection
FDDA may also pose a potential risk to future site residents or facility workers.
Under this alternative, no remedial actions will be conducted to reduce
concentrations in soil or groundwater to RAOs, therefore the potential future risk to
trespassers, site residents, facility workers and/or construction workers will remain
and RAOs will not be achieved.
The results of the ecological risk assessment indicated that select SVOCs and VOCs
in soil within the FDDA may pose potential risk to ecological receptors.
Ecological Protection
Under this alternative, no remedial actions will be conducted to reduce
concentrations to meet cleanup goals therefore the potential future risk to ecological
receptors will remain and RAOs will not be achieved.
COMPLIANCE WITH ARARs *
Under existing conditions, concentrations of select compounds in soil and
Chemical Specific
groundwater exceed chemical specific ARARs. Contaminant concentrations in soil
and groundwater are not anticipated to reduce significantly in the foreseeable
future; therefore, chemical specific ARARs will not be met for this alternative.
Location specific ARARs do not apply for this alternative since there are no
Location Specific
remedial activities associated with this alternative that will cause adverse impacts to
natural resources.
Action Specific
Action specific ARARs do not apply for this alternative since there are no remedial
activities associated with this alternative.
LONG-TERM EFFECTIVENESS AND PERMANENCE
Since there are no active remedial actions or institutional controls associated with
Magnitude of Residual Risk
this alternative, potential future exposure to site residents, facility workers,
construction workers and ecological receptors to contaminants in soil and
groundwater will continue to pose a potential residual risk.
Adequacy and Reliability of
Controls
No controls are proposed for this alternative.
REDUCTION OF TOXICITY, MOBILITY AND VOLUME THROUGH TREATMENT
Treatment Process Used and
Materials Treated
No active treatment is proposed for this alternative.
Amount Destroyed or Treated
None
Degree of Expected Reductions
No active treatment is proposed for this alternative, therefore, no reduction in
in Toxicity, Mobility or Volume
toxicity, mobility or volume through treatment will be achieved with this
through Treatment
alternative,
FDDA-1
-------
TABLE FDDA-1
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table FDDA-1: No Action
EVALUATION CRITERIA
DETAILED ANALYSIS
Degree to which Treatment is
Irreversible
No treatment is proposed.
Type and Quantity of Residuals
Remaining after Treatment
Existing conditions will remain since no treatment is proposed.
Degree to Which Treatment
Reduces Principal Threats
No treatment is proposed.
SHORT-TERM EFFECTIVENESS
Protection of Community During
Remedial Action
Not applicable since no remedial actions are included in this alternative.
Protection of Workers During
Remedial Action
Not applicable since no remedial actions are included in this alternative.
Environmental Impacts
Not applicable since no remedial actions are included in this alternative.
Time Until Remedial Action
Objectives are Achieved
No remedial actions will be implemented to reduce concentrations in soil or
groundwater to cleanup goals Therefore, RAO's will not be achieved through
implementation of this alternative.
IMPLEMENTABILITY
Ability to Construct and Operate
the Technology
Not applicable since no remedial actions are included in this alternative.
Reliability of the Technology
Not applicable since no remedial actions are included in this alternative.
Ease of Undertaking Additional
Remedial Actions, if necessary
This alternative will not limit or interfere with the ability to implement or perform
future remedial actions.
Ability to Monitor Effectiveness
of Remedy
Not applicable since no remedial actions or monitoring are included in this
alternative.
Ability to Obtain Approvals arid
Coordinate with Other Agencies
Not applicable since no remedial actions are included in this alternative; therefore,
no approvals or coordination required.
Availability of off-site
Treatment, Storage and Disposal
Services and Capacity
Not applicable for this alternative.
Availability of Necessary
Equipment and Specialists
No equipment or specialists required for this alternative,
Availability of Technology
Not applicable since no remedial technologies will be used.
COSTS - net present value (7%)
Capital Costs
$0
Annual Operation, Maintenance
and Monitoring
$41,000
Periodic Costs
$43,000
TOTAL
$84,000
FDDA-1
-------
TABLE FDDA-2
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table FDDA-2: Containment of soil (with cap) and hydraulic containment of groundwater (through
extraction and ex-situ treatment)
EVALUATION CRITERIA
DETAILED ANALYSIS
OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT
The results of the human health risk assessment indicated that VOCs and SVOCs in soil may
pose a potential risk to receptors. The potential for volatilization of select VOCs in
groundwater may pose a potential risk to future site residents or facility workers. If groundwater
is used as a source of potable water, groundwater in the FDDA may also pose a potential risk to
future site residents or facility workers.
Human Health Protection
Under this alternative, an engineered barrier will be constructed to eliminate human exposure
via direct contact and volatilization from soil and groundwater. A groundwater extraction and
ex-situ treatment system to hydraulically contain impacted groundwater and reduce the mass of
contaminants in groundwater will also be implemented. Hydraulic containment of groundwater
will prevent downgradient migration and exposure. Institutional controls will also be
implemented to control ingestion and direct exposure to soil and groundwater. 1
Ecological Protection
The results of the ecological risk assessment indicated that select SVOCs and VOCs in soil
within the FDDA may pose potential risk to ecological receptors.
Under this alternative, containment of the impacted soil through an engineered barrier will be
constructed to control ecological exposure.
COMPLIANCE WITH ARARs
Chemical Specific
Under existing conditions, concentrations of select compounds in soil and groundwater exceed
chemical specific ARARs. This alternative will prevent exposure to the impacted material, but
will not meet the PRGs established and therefore not comply with the chemical specific ARARs.
Location Specific
Potential location specific ARARs for this alternative are presented in Table E-2 in Appendix E;
this alternative will be designed and implemented to comply with applicable location-specific
ARARs.
Action Specific
Action specific ARARs for this alternative are presented in Table E-2 in Appendix E; this
alternative will be designed and implemented to comply with applicable action-specific ARARs.
LONG-TERM EFFECTIVENESS AND PERMANENCE
Magnitude of Residual Risk
The impacted soil will remain beneath the containment barrier, which will reduce the potential
for future leaching into groundwater over time. Hydraulic containment of impacted groundwater
will reduce residual risk, preventing downgradient exposure while actively reducing the mass of
dissolved contaminants in groundwater. However, since impacted soil will remain in the
FDDA, residual risk is moderate to high compared to other alternatives.
Adequacy and Reliability of
Controls
Assuming effective implementation, institutional controls should effectively limit human
exposure to impacted soil and groundwater until RAOs are achieved. Monitoring of the
extraction system's effectiveness in hydraulically containing the plume will be required to
determine the reliability of the groundwater component of this alternative and routine inspection
that the containment barrier is intact will be required to determine the reliability of the soil
component of this alternative.
FDDA-2
-------
TABLE FDDA-2
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table FDDA-2: Containment of soil (with cap) and hydraulic containment of groundwater (through
extraction and ex-situ treatment)
EVALUATION CRITERIA
DETAILED ANALYSIS
REDUCTION OF TOXICITY, MOBILITY AND VOLUME THROUGH TREATMENT - .' : S?
Treatment Process Used and
Materials Treated
This alternative does not treat the impacted soil. Materials treated within groundwater through
the hydraulic containment extraction and ex-situ treatment system will include VOCs, SVOCs &
metals via a combination of technologies such as air stripping, advanced oxidation processes
and/or metals treatment, in addition to one or more pretreatment steps (to be determined during
remedial design phase).
Amount Destroyed or Treated
No soil will be treated, but an estimated total extraction rate of 20 gpm of groundwater will be
treated through the hydraulic containment groundwater extraction and ex-situ treatment system.
Current dissolved concentrations indicate an estimated 1,600 to 2,000 lbs of VOCs in i'DDA
groundwater available for treatment. With the soil remaining in-situ, the potential exists for
future leaching of additional contaminants from soil to groundwater.
Degree of Expected Reductions
in Toxicity, Mobility or Volume
through Treatment
Compared to other alternatives evaluated for the FDDA, this alternative provides a minimal
level of reduction in toxicity, and volume and a moderate level of reduction in mobility of
contaminants through treatment.
Degree to which Treatment is
Irreversible
No soil will be actively treated. The groundwater treatment will be permanent.
Type and Quantity of Residuals
Remaining after Treatment
Treatment of the groundwater plume and any resulting VOC vapors will result in a minimal
volume of treatment residuals that will require off-site treatment/disposal at a licensed facility.
Degree to Which Treatment
Reduces Principal Threats
Principal threats of soil exposure and potential leaching from soil to groundwater are not
addressed via treatment for this alternative; however, in conjunction with institutional controls,
the extraction and treatment of contaminants in groundwater will reduce the principal threats/
exposure risks.
SHORT-TERM EFFECTIVENESS
Protection of Community During
Remedial Action
Construction of the soil containment barrier and construction and operation of the on-site
groundwater treatment facility will not have significant short-term impacts on the local
community.
Protection of Workers During
Remedial Action
Work will be performed in accordance with applicable OS HA standards. Site-specific health
and safety plan(s) will be developed to protect site workers.
Environmental Impacts
Impacts to the wetland resource areas are anticipated to be moderate (compared to other
alternatives) during construction activities due to the location of the extraction wells and the
containment barrier within and/or adjacent to the resource area. Once the containment barrier
and the groundwater treatment system are installed, operation and monitoring activities are
anticipated to have limited impacts. Available practical means such as erosion and stormwater
control measures will also be implemented to minimize harm to wetland areas during
construction.
Time Until Remedial Action
Objectives are Achieved
The estimated time to achieve RAOs with this alternative is approximately
30 to 134 years
FDDA-2
-------
TABLE FDDA-2
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table FDDA-2: Containment of soil (with cap) and hydraulic containment of groundwater (through
extraction and ex-situ treatment)
EVALUATION CRITERIA DETAILED ANALYSIS
- ; IMPLEMENTABILITV -
The installation of wells and piping for the hydraulic containment groundwater treatment system
involves common construction techniques; however due to the location of the impacted
groundwater within and adjacent to the wetland resource area, this alternative poses difficulty in
implementation to reduce environmental impacts and in designing the treatment system layout.
Ability to Construct and Operate prjor implementation, pre-design pilot studies will be required to determine groundwater
the Technology capture zones. Construction of a soil containment barrier involves common construction
techniques. Stormwater/ drainage features will be required as part of the design.
Hydraulic containment through groundwater extraction is a demonstrated and reliable method
for capturing and collecting impacted groundwater. In addition, available ex-situ treatment
Reliability of the Technology components are effective in treating groundwater to meet discharge limits. Institutional controls
and containment barriers are common and reliable technologies to reduce/eliminate exposure to
impacted soil and groundwater.
Ease of Undertaking Additional
Remedial Actions, if necessary
Utilizing the area as a stormwater management basin for the Northern lobe final cover system
and leaving the soil in place will present significant difficulty in undertaking additional remedial
actions due to access restrictions.
Groundwater monitoring to demonstrate contaminant reduction is easily implementable.
Ability to Monitor Effectiveness
Treatment system effluent will be monitored on a routine basis to evaluate the effectiveness of
of Remedy
the treatment system and document that discharge requirements are being met.
Routine inspection of the soil containment barrier is easily implementable as well.
Ability to Obtain Approvals and
Coordinate with Other Agencies
The remedial action will be designed and implemented under coordination with appropriate
Federal and State agencies.
Availability of off-site
Treatment, Storage and Disposal
No off-site treatment, storage or disposal services required for the soil component of the
alternative. Discharge of the treated groundwater will be to surface water or the local POTW.
Services and Capacity
Availability of Necessary
Equipment, materials and services for this alternative are readily available.
Equipment and Specialists
Availability of Technology
Qualified engineers and contractors are available to design and implement this alternative.
COSTS - net present value (7%)
Capital Costs
$3,100,000
Annual Operation, Maintenance
and Monitoring
$4,300,000 lo 15,100,000
Periodic Costs
$130,000
TOTAL
$7,530,000 to $8,330,000
O&M cost range based on discharge method - tow end to surface water, high end to POTW
FDDA-2
-------
TABLE FDDA-3
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table FDDA-3: Excavation, treatment and/or disposal of soil with hydraulic containment of
groundwater (through extraction and ex-situ treatment)
EVALUATION CRITERIA
DETAILED ANALYSIS
OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT
The results of the human health risk assessment indicated that VOCs and SVOCs in soil may
pose a potential risk to receptors. The potential for volatilization of select VOCs in
groundwater may pose a potential risk to future site residents or facility workers. If groundwater
is used as a source of potable water, groundwater in the FDDA may also pose a risk to future site
residents or facility workers.
Human Health Protection
Under this alternative, excavation of the impacted soil will be conducted to reduce
concentrations to meet RAOs, therefore eliminating the potential human health risks associated
with the impacted soil and achieving site RAOs for soil. In addition, a groundwater extraction
and existing treatment system to hydraulically contain impacted groundwater and reduce the
mass of contaminants in groudnwater will also be implemented. Hydraulic containment of
groundwater will prevent downgradient migration and exposure. Institutional controls will
also be implemented to reduce/prevent exposure to groundwater.
Ecological Protection
The results of the ecological risk assessment indicated that select SVOCs and VOCs in soil
within the FDDA may pose potential risk to ecological receptors.
Under this alternative, excavation of the impacted soil will be conducted to meet cleanup goals.
Therefore the potential future risk to ecological receptors will be eliminated and RAOs for soil
will be achieved.
COMPLIANCE WITH ARARs
Chemical Specific
Potential chemical specific ARARs for this alternative are presented in Table E-2 in Appendix
E; this alternative will be designed and implemented to comply with applicable chemical-
specific ARARs.
Location Specific
Potential location specific ARARs for this alternative are presented in Table E-2 in Appendix E;
this alternative will be designed and implemented to comply with applicable location-specific
ARARs.
Action Specific
Action specific ARARs for this alternative are presented in Table E-2 in Appendix E; this
alternative will be designed and implemented to comply with applicable action-specific ARARs.
LONG-TERM EFFECTIVENESS AND. PERMANENCE —
Magnitude of Residual Risk
The removal of impacted soil will significantly reduce residual risks due to this media.
Hydraulic containment of impacted groundwater will significantly reduce residual risk,
preventing downgradient exposure, while reducing the mass of contaminants in groundwater.
Therefore, residual risk is low compared to other alternatives (e.g., FDDA-2).
Adequacy and Reliability of
Controls
Excavation of impacted soil will provide long-term effectiveness and permanence since the
material will be removed. Post excavation confirmatory soil samples will be collected to
document the reliability of the removal.
Assuming effective implementation, institutional controls should effectively limit human
exposure to impacted groundwater until groundwater RAOs are achieved. Monitoring of the
extraction system's effectiveness in hydraulically containing the plume will be required to 1
measure the reliability of the groundwater component of this alternative. 1
FDDA-3
-------
TABLE FDDA-3
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table FDDA-3: Excavation, treatment and/or disposal of soil with hydraulic containment of
groundwater {through extraction and ex-situ treatment)
EVALUATION CRITERIA DETAILED ANALYSIS
REDUCTION OF TOXICITY, MOBILITY AND VOLUME THROUGH TREATMENT !
Treatment of the excavated soil may or may not be required prior to disposal; depending on the
waste characterization results of the material being excavated, ex-situ treatment of soil may be
implemented prior to disposal.
Treatment Process Used and
Materials Treated Materials treated within groundwater through the hydraulic containment extraction and ex-situ
treatment system will include VOCs, SVOCs & metals via a combination of technologies such
as air stripping, advanced oxidation processes and/or metals treatment, in addition to one or
more pretreatment steps (to be determined during remedial design phase).
Treatment of a portion of the excavated soil may be required prior to disposal; however, the
volume or concentrations will be dependent on waste characterization analysis. An estimated
total extraction rate of 24 gpm of groundwater will be treated through the hydraulic containment
Amount Destroyed or Treated groundwater extraction and ex-situ treatment system. Current dissolved concentrations indicate
an estimated 1.600 to 2,000 lbs of VOCs in FDDA groundwater available for treatment.
Treatment ofa portion of the excavated soil may be required prior to disposal; however, the
volume or concentrations will be dependent on waste characterization analysis.
Degree of Expected Reductions
in Toxicity, Mobility or Volume Compared to other alternatives evaluated for the FDDA, this alternative provides a moderate
through Treatment level of reduction in toxicity, mobility and volume of contaminants through groundwater
treatment.
Degree to which Treatment is
Irreversible
The groundwater and if required, soil treatment will be permanent.
Type and Quantity of Residuals
Remaining after Treatment
Through excavation of the impacted soil, no residuals presenting exposure risks will remain.
Treatment of the groundwater plume and any resulting VOC vapors will result in a low to
moderate volume of treatment residuals that will require off-site treatment/disposal at a licensed
facility.
Degree to Which Treatment
Reduces Principal Threats
Principal threats of soil exposure and potential leaching from soil to groundwater are not
addressed via treatment for this alternative; however, through source excavation, institutional
controls, and hydraulic containment of groundwater (through groundwater extraction and
treatment), the principal threats/ exposure risks will be controlled.
SHORT-TERM EFFECTIVENESS
This alternative will not have significant short-term effects on the local community. Re-
Protection of Community Durine use/disposal of the material on-site is anticipated beneath the landfill final cover system;
Remedial Action however, should off-site treatment be required, local truck/ vehicular traffic will increase during
implementation.
Protection of Workers During
Remedial Action
Work will be performed in accordance with applicable OSHA standards. Site-specific health
and safety plan(s) will be developed to protect site workers,
Environmental Impacts
Impacts to the wetland resource areas are anticipated to be moderate during construction
activities due to the location of the extraction wells and the excavation extent within and/or
adjacent to the wetland resource area. Once the excavation is complete, the groundwater
treatment system is installed, and the area restored, operation and monitoring activities are
anticipated to have limited to no impacts. Available practical means such as erosion and
stormwater control measures will also be implemented to minimize harm to wetland areas
during construction.
FDDA-3
-------
TABLE FDDA-3
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table FDDA-3: Excavation, treatment and/or disposal of soil with hydraulic containment of
groundwater (through extraction and ex-situ treatment)
EVALUATION CRITERIA
DETAILED ANALYSIS
Time Until Remedial Action
Objectives are Achieved
Soil RAOs will be achieved upon removal of the impacted soil; confirmatory soil sampling will
be performed to document the achievement of soil RAOs.
The estimated time to achieve groundwater RAOs is approximately
24 to 89 years
IMPLEMENTABILITY
Soil excavation involves common techniques that are straight forward to implement. Erosion
controls will be required as part of the design and implementation to reduce environmental
impacts to the adjacent wetlands.
Ability to Construct and Operate ''^c installation of wells and piping for the hydraulic containment groundwater treatment system
the Teehnoloev involves common construction techniques; however due to the location of the impacted
groundwater within and adjacent to the wetland resource area, this alternative poses difficulty in
implementation to reduce environmental impacts and in designing the treatment system layout.
Prior to implementation, pre-design pilot studies will be required to determine groundwater
capture zones.
Reliability of the Technology
Excavation of impacted soil is a reliable technology to quickly and effectively eliminate
exposure risks and remove mass. Implementation of institutional controls is a common and
reliable component of the remedy to control exposure to impacted groundwater. Hydraulic
containment through groundwater extraction is a demonstrated and reliable method for capturing
and collecting impacted groundwater. In addition, available ex-situ treatment components are
effective in treating groundwater to meet discharge limits.
Ease of Undertaking Additional
Remedial Actions, if necessary
This alternative wil
remedial actions.
not limit or interfere with the ability to implement or perform future
Confirmatory soil sampling and analysis is easily imple men table to measure the effectiveness of
the soil component of this alternative. Groundwater monitoring to demonstrate contaminant
Ability to Monitor Effectiveness reduction is easily implementable. Treatment system effluent will be monitored on a routine
of Remedy basis to evaluate the effectiveness of the treatment system and document that discharge
requirements are being met.
, The remedial action will be designed and implemented under coordination with appropriate
Ability to Obtain Approvals and .. . . '
„ .. . , _ , . . Federal and State agencies.
Coordinate with Other Agencies
Availability of off-site
Treatment, Storage and Disposal
Services- and Capacity
Facilities are available to treat or dispose of the excavated material within the northeast.
However, it is assumed that excavated soil will be reused/disposed of on-site at one of the
landfill lobes beneath the final cover system. Discharge of the treated groundwater will be to
surface water or the local POTW.
FDDA-3
-------
TABLE FDDA-3
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table FDDA-3: Excavation, treatment and/or disposal of soil with hydraulic containment of
groundwater (through extraction and ex-situ treatment)
EVALUATION CRITERIA
DETAILED ANALYSIS
Availability of Necessary
Equipment, materials and services for this alternative are readily available.
Equipment and Specialists
Availability of Technology
Qualified engineers and contractors are available to design and implement this alternative.
COSTS - net present value (7%)
Capital Costs
$3,400,000
Annual Operation, Maintenance
and Monitoring
$4,100,000 to $5,700,000
Periodic Costs
$120,000
TOTAL
$7,620,000 to $9,220,000
O&M cost range based on discharge method - low end to surface water, high end to POTW
FDDA-3
-------
TABLE FDDA-4
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table FDDA-4: Excavation, treatment and/or disposal of soil with groundwater treatment (focused
mass reduction)
EVALUATION CRITERIA
DETAILED ANALYSIS
OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT
Human Health Protection
The results of the human health risk assessment indicated that VOCs and SVOCs in soil may pose
a potential risk to receptors. The potential for volatilization of select VOCs in groundwater may
pose a potential risk to future site residents or facility workers, if groundwater is used as a source
of potable water, groundwater in the FDDA may also pose a risk to future site residents or facility
workers.
Under this alternative, excavation of the impacted soil will be conducted to reduce concentrations
to meet RAOs therefore eliminating the potential human health risks associated with the impacted
soil and achieving site RAOs for soil. In situ natural attenuation mechanisms will be monitored to
address groundwater impacts following a phased approach to the groundwater remedy.
Ecological Protection
The results of the ecological risk assessment indicated that select SVOCs and VOCs in soil within
the FDDA may pose potential risk to ecological receptors. Under this alternative, excavation of
the impacted soil will be conducted to meet cleanup goals therefore the potential future risk to
ecological receptors will be eliminated and RAOs for soil will be achieved.
COMPLIANCE WITH ARARs
Chemical Specific
Potential chemical specific ARARs for this alternative are presented in Table E-2 in Appendix E;
this alternative will be designed and implemented to comply with applicable chemical-specific
ARARs.
Location Specific
Potential location specific ARARs for this alternative are presented in Table E-2 in Appendix E;
this alternative will be designed and implemented to comply with applicable location-specific
ARARs.
Action Specific
Action specific ARARs for this alternative are presented in Table E-2 in Appendix E; this
alternative will be designed and implemented to comply with applicable action-specific ARARs.
LONG-TERM EFFECTIVENESS AND PERMANENCE
Magnitude of Residual Risk
Removal of the impacted soil through excavation will significantly reduce residual risk associated
with the impacted soil and minimize the potential for future leaching of contaminants from soil to
groundwater. A phased groundwater remedial action will further reduce residual risk over time.
Therefore, residual risk is low to moderate compared to other alternatives.
Adequacy and Reliability of
Controls
Excavation of impacted soil will provide long-term effectiveness and permanence since the
material will be removed. Post excavation confirmatory soil samples will be collected to
document the reliability of the removal.
Assuming effective implementation, institutional controls should effectively limit human exposure
to impacted groundwater until groundwater RAOs are achieved. Monitoring of the MNA
program's effectiveness will be required to measure the reliability of the groundwater component
of this alternative.
FDDA-4
-------
TABLE FDDA-4
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table FDDA-4: Excavation, treatment and/or disposal of soil with groundwater treatment (focused
mass reduction)
EVALUATION CRITERIA
DETAILED ANALYSIS
REDUCTION OF TOXICITY, MOBILITY AND VOLUME THROUGH TREATMENT
Treatment of the excavated soil may or may not be required prior to on-site disposal; depending
on the waste characterization results of the material being excavated, ex-situ treatment of soil may
be implemented prior to disposal beneath the landfill final cover system.
Treatment Process Used and
Materials Treated
Natural attenuation processes, including biodegradation. dispersion, dilution, adsorption,
volatilization and/or chemical and biological stabilization or destruction of contaminants, will
address groundwater COPCs in situ. Following the phased approach, this alternative may also
include an active groundwater treatment component.
Amount Destroyed or Treated
Treatment of a portion of the excavated soil may be required prior to disposal; however, the
volume or concentrations will be dependent on waste characterization analysis. Current dissolved
concentrations indicate an estimated 1,600 to 2,000 lbs of VOCs in FDDA groundwater. Natural
attenuation processes will address the dissolved plume through biodegradation, dispersion,
dilution, adsorption, volatilization and/or chemical and biological stabilization or destruction.
Active groundwater treatment system will be implemented, if needed following the phased
approach.
Degree of Expected Reductions
in Toxicity, Mobility or Volume
through Treatment
Treatment of a portion of the excavated soil may be required prior to disposal beneath the landfill
final cover system; however, the volume or concentrations will be dependent on waste
characterization analysis.
Degree to which Treatment is
Irreversible
If required, groundwater and soil treatment will be permanent.
Type and Quantity of Residuals
Remaining after Treatment
Through excavation of the impacted soil, no residuals presenting exposure risks will remain With
natural attenuation of groundwater, there will be no residuals requiring disposal.
Degree to Which Treatment
Reduces Principal Threats
Principal threats of soil exposure and potential leaching from soil to groundwater are not
addressed via treatment for this alternative; however, through source excavation, institutional
controls, and natural attenuation mechanisms, the principal threats/ exposure risks will be
controlled.
SHORT-TERM EFFECTIVENESS . . ,
Protection of Community During
Remedial Action
This alternative will not have significant short-term effects on the local community. Re-
use/disposal of soil on-site is anticipated beneath the landfill final cover system; however, should
off-site treatment be required, local truck/ vehicular traffic will increase during implementation.
Protection of Workers During
Remedial Action
Work will be performed in accordance with applicable OSI1A standards. Site-specific health and
safety plan(s) will be developed to protect site workers.
Environmental Impacts
Impacts to the wetland resource areas are anticipated to be low to moderate during construction
activities due to the location of the excavation extent within and/or adjacent to the wetland
resource area. Once the excavation is complete and the area restored, monitoring activities are
anticipated to have limited to no impacts. Available practical means such as erosion and
stormwater control measures will also be implemented to minimize harm to wetland areas during
construction.
FDDA-4
-------
TABLE FDDA-4
DETAJLED ANALYsiS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table FDDA-4: Excavation, treatment and/or disposal of soil with groundwater treatment (focused
mass reduction)
EVALUATION CRITERIA
DETAILED ANALYSIS
Soil RAOs will be achieved upon removal of the impacted soil; confirmatory soil sampling will be
Time Until Remedial Action
Objectives are Achieved
performed to document the achievement of RAOs.
The estimated time to achieve groundwater RAOs is approximately
36 to 103 years
IMPLEMENTABILITY
Soil excavation involves common techniques that are straight forward to implement. Erosion
controls will be required as part of the design and implementation to reduce environmental
Ability to Construct and Operate
impacts to the adjacent wetlands.
the Technology
If implemented, the installation of wells and piping for the focused groundwater extraction and ex-
situ treatment system involves common construction techniques. Prior to implementation, pre-
design pilot studies will be required to determine groundwater capture zones.
Excavation of impacted soil is a reliable technology to quickly and effectively eliminate exposure
Reliability of the Technology
risks and remove mass. Implementation of institutional controls is a common and reliable
component of the remedy to eliminate exposure to impacted groundwater and natural attenuation
processes have demonstrated effective reduction in FDDA groundwater.
Ease of Undertaking Additional
This alternative would not limit or interfere with the ability to implement or perform future
remedial actions.
Remedial Actions, if necessary
Confirmatory soil sampling and analysis is easily implementable to measure the effectiveness of
Ability to Monitor Effectiveness
of Remedy
the soil component of this alternative. Groundwater monitoring to demonstrate contaminant
reduction is easily implementable. Treatment system effluent (if required) will be monitored on a
routine basis to evaluate the effectiveness of the treatment system and document that discharge
requirements arc beine met.
Ability to Obtain Approvals and
Coordinate with Other Agencies
The remedial action will be designed and implemented under coordination with appropriate
Federal and State agencies.
Facilities are available to treat or dispose of the excavated material within the northeast.
Availability of off-site Treatment, However, it is assumed that excavated soil will be reused on-site at one of the landfill lobes
Storage and Disposal Services
and Capacity
beneath the final cover system. If groundwater extraction and ex-situ treatment is implemented
(through phased approach), discharge of the treated groundwater will be to surface water or the
local POTW.
Availability of Necessary
Equipment, materials and services for this alternative are readily available.
Equipment and Specialists
Availability of Technology
Qualified engineers and contractors are available to design and implement this alternative.
COSTS - net present value 1
Capital Costs
$1,000,000
Annual Operation, Maintenance
and Monitoring
51,700,000
Periodic Costs
$110,000
TOTAL
$2,810,000
FDDA-4
-------
TABLE FDDA-5
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table FDDA-5: Excavation, treatment and/or disposal of soil with groundwater extraction and ex-
situ treatment for area-wide contaminant reduction
EVALUATION CRITERIA
DETAILED ANALYSIS
OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT
The results of the human health risk assessment indicated that VOCs and SVOCs in soil may
pose a potential risk to receptors. The potential for volatilization of select VOCs in
groundwater may pose a potential risk to future site residents or facility workers. If groundwater
is used as a source of potable water, groundwater in the FDD A may also pose a risk to future site
residents or facility workers.
Human Health Protection
Under this alternative, excavation of the impacted soil will be conducted to reduce
concentrations to meet RAOs therefore eliminating the potential human health risks associated
with the impacted soil and achieving site RAOs for soil. In addition to soil excavation, a
groundwater extraction and treatment system for area-wide contaminant reduction/restoration
and institutional controls will also be implemented to address impacted groundwater.
Ecological Protection
The results of the ecological risk assessment indicated that select SVOCs and VOCs in soil
within the FDDA may pose potential risk to ecological receptors.
Under this alternative, excavation of the impacted soil will be conducted to reduce
concentrations to meet cleanup goals. Therefore the potential future risk to ecological receptors
will be eliminated and RAOs for soil will be achieved.
COMPLIANCE WITH ARARs
Chemical Specific
Potential chemical specific ARARs for this alternative are presented in Table E-2 in Appendix.
E; this alternative will be designed and implemented to comply with applicable chemical-
specific ARARs.
Location Specific
Potential location specific ARARs for this alternative are presented in Table E-2 in Appendix E;
this alternative will be designed and implemented to comply with applicable location-specific
ARARs.
Action Specific
Action specific ARARs for this alternative are presented in Table E-2 in Appendix E: this
alternative will be designed and implemented to comply with applicable action-specific ARARs.
LONG-TERM EFFECTIVENESS AND PERMANENCE
Magnitude of Residual Risk
Area-wide contaminant reduction of impacted groundwater through groundwater extraction and
ex situ treatment will significantly reduce residual risk, preventing downgradient exposure and
actively treating impacted groundwater, in addition, removal of the impacted soil through
excavation will significantly reduce any residual risk associated with the impacted soil.
Therefore, residual risk is low compared to other alternatives.
FDDA-5
-------
TABLE FDDA-5
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table FDDA-5; Excavation, treatment and/or disposal of soil with groundwater extraction and ex-
situ treatment for area-wide contaminant reduction
EVALUATION CRITERIA
DETAILED ANALYSIS
Excavation of impacted soil will provide long-term effectiveness and permanence since the
material will be removed. Post excavation confirmatory soil samples will be collected to
document the reliability of the alternative.
Adequacy and Reliability of
Controls
Assuming effective implementation, institutional controls should effectively limit human
exposure to impacted groundwater until groundwater RAOs are achieved. Monitoring of the
extraction system's effectiveness in reducing contaminant mass will be required to measure the
reliability of the groundwater component of this alternative.
REDUCTION OF TOXICITY, MOBILITY AND VOLUME THROUGH TREATMENT - ; i ^
Treatment Process Used and
Materials Treated
Treatment of the excavated soil may or may not be required prior to disposal; depending on the
waste characterization results of the material being excavated, ex-situ treatment of soil may be
implemented prior to disposal..
Materials treated within groundwater through the extraction and ex-situ treatment system will
include VOCs, SVOCs & metals via a combination of technologies such as air stripping,
advanced oxidation processes and/or metals treatment, in addition to one or more pretreatment
steps (to be determined during remedial design phase).
Amount Destroyed or Treated
Treatment of a portion of the excavated soil may be required prior to disposal; however, the
volume or concentrations will be dependent on waste characterization analysis. An estimated
total extraction rate of 50 gpm of groundwater will be treated through the groundwater
extraction and ex-situ treatment system. Current dissolved concentrations indicate an estimated
1,600 to 2,000 lbs of VOCs in FDD A groundwater available for treatment.
Degree of Expected Reductions
in Toxicity, Mobility or Volume
through Treatment
Treatment of a portion of the excavated soil may be required prior to disposal; however, the
volume or concentrations will be dependent on waste characterization analysis.
Compared to other alternatives evaluated for the FDD A. this alternative provides a moderate to
high level of reduction in toxicity, mobility and volume of contaminants through groundwater
treatment.
Degree to which Treatment is
Irreversible
The groundwater and, if required, soil treatment will be permanent.
Type and Quantity ot" Residuals
Remaining after Treatment
Through excavation of the impacted soil, no residuals presenting exposure risks will remain.
Treatment of the groundwater plume and any resulting VOC vapors will result in a moderate to
high volume of treatment residuals that will require off-site treatment/disposal at a licensed
facility.
Degree to Which Treatment
Reduces Principal Threats
Principal threats of soil exposure and potential leaching from soil to groundwater are not
addressed via treatment for this alternative; however, through excavation, institutional controls,
and groundwater extraction and treatment, the principal threats/ exposure risks will be
eliminated over time.
SHORT-TERM EFFECTIVENESS
This alternative will not have significant short-term effects on the local community. Re-
Protection of Community During use/disposal of the material on-site is anticipated beneath the landfill final cover system;
Remedial Action however, should off-site treatment be required, local truck/ vehicular traffic will increase during
implementation.
FDDA-5
-------
TABLE FDDA-5
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table FDDA-5: Excavation, treatment and/or disposal of soil with groundwater extraction and ex-
situ treatment for area-wide contaminant reduction
EVALUATION CRITERIA
DETAILED ANALYSIS
Protection of Workers During
Remedial Action
Work will be performed in accordance with applicable OSHA standards. Site-specific health
and safety plan(s) will be developed to protect site workers.
Environmental Impacts
Impacts to the wetland resource areas are anticipated to be moderate to high during construction
activities due to the location of the extraction wells and the excavation extent within and/or
adjacent to the wetland resource area. Once the excavation is complete, the groundwater
treatment system is installed, and the area restored, operation and monitoring activities are
anticipated to have limited impacts. Available practical means such as erosion and stormwater
control measures will also be implemented to minimize harm to wetland areas during
construction.
Time Until Remedial Action
Objectives are Achieved
Soil RAOs will be achieved upon removal of the impacted soil; confirmatory soil sampling will
be performed to document the achievement of RAOs.
The estimated time to achieve groundwater RAOs is approximately
23 to 85 years
IMPLEMENTABILITY . -
Soil excavation involves common techniques that are straight forward to implement. Erosion
controls will be required as part of the design and implementation to reduce environmental
impacts to the adjacent wetlands.
Ability to Construct and Operate
the Technology
The installation of wells and piping for the groundwater treatment system involves common
construction techniques; however due to the location of the impacted groundwater within and
adjacent lo the wetland resource area, this alternative poses difficulty^n implementation to
reduce environmental impacts and in designing the treatment system layout. Prior to
implementation, pre design pilot studies will be required to measure groundwater capture zones.
Reliability of the Technology
Excavation of impacted soil is a reliable technology to quickly and effectively eliminated
exposure risks. Implementation of institutional controls is a common and reliable component of
the remedy to control exposure to impacted groundwater. Contaminant mass reduction through
groundwater extraction is a demonstrated and reliable method for capturing and collecting
impacted groundwater. In addition, available ex-situ treatment components (are effective in
treating groundwater to meet remedial goals.
Ease of Undertaking Additional
Remedial Actions, if necessary
This alternative will not limit or interfere with the ability to implement or perform future
remedial actions.
Confirmatory soil sampling and analysis is easily implementable to measure ihe effectiveness of
the soil component of this alternative.
Ability lo Monitor Effectiveness
of Remedy Groundwater monitoring to demonstrate contaminant reduction is easily implementable.
Treatment system effluent will be monitored on a routine basis to evaluate the effectiveness of
the treatment system and document that discharge requirements are being met.
,.... „ . . I j The remedial action will be designed and implemented under coordination with appropriate
Ability to Obtain Approvals and e ' l r '
„ .. ¦ . . • Federal and State agencies.
Coordinate with Other Agencies
FDDA-5
-------
TABLE FDDA-5
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table FDDA-5: Excavation, treatment and/or disposal of soil with groundwater extraction and ex-
situ treatment for area-wide contaminant reduction
EVALUATION CRITERIA
DETAILED ANALYSIS
Availability of off-site
Treatment, Storage and Disposal
Services and Capacity
Facilities are available to treat or dispose of the excavated material within the northeast.
However, it is assumed that excavated soil will be reused on-site at one of the landfill lobes
beneath the final cover system. Discharge of the treated groundwater will be lo surface water or
the local POTW,
Availability of Necessary
Equipment, materials and services for this alternative are readily available.
Equipment and Specialists
Availability of Technology
Qualified engineers and contractors are available to design and implement this alternative.
C0S1S - net present value {7%)
Capital Costs
$4,500,000
Annual Operation, Maintenance
and Monitoring
$5,300,000 to $7,700,000
Periodic Costs
$130,000
TOTAL
$9,930,000 to $12,330,000
(MM cost range based on discharge method - low end to surface water, high end to POTW
FDDA-5
-------
TABLE GSA-1
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table GSA-1: No Action
EVALUATION CRITERIA
DETAILED ANALYSIS
OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT
The results of the human health risk assessment indicated that select metals and
PAT Is in soils may pose a potential future risk to site residents, facility workers
and/or construction workers.
Human Health Protection
Under this alternative, no remedial actions will be conducted to reduce
concentrations of PAlIs or metals in soil to cleanup goals. Therefore the potential
future risk to site residents, facility workers and/or construction workers will remain
and RAOs will not be achieved.
The resutts of the ecological risk assessment indicated that current and potential
future risks to ecological receptors are present in soil in the GSA.
Ecological Protection
Under this alternative, no remedial actions will be conducted to reduce
concentrations in soil to cleanup goals. Therefore the potential future risk to
ecological receptors will remain and RAOs will not be achieved.
COMPLIANCE WITH ARARs ¦ ^
Chemical Specific
Under existing conditions, constituents in soil exceed chemical specific ARARs.
Contaminant concentrations in soil are not anticipated to reduce over time;
therefore, chemical specific ARARs will not be met for this alternative,
Location Specific
Location specific ARARs do not apply for this alternative since there are no
remedial activities associated with this alternative that will cause adverse impacts to
natural resources.
Action Specific
Action specific ARARs do not apply for this alternative since there are no remedial
activities associated with this alternative.
LONG-TERM EFFECTIVENESS AND PERMANENCE
Magnitude of Residual Risk
Since there are no active remedial actions or institutional controls associated with
this alternative, potential future exposure to site residents, facility workers,
construction workers and ecological receptors to contaminants in soil will continue
to pose a potential residual risk.
Adequacy and Reliability of
Controls
No controls are proposed for this alternative.
REDUCTION OF TOXICITY, MOBILITY AND VOLUME THROUGH TREATMENT
Treatment Process Used and
Materials Treated
No active treatment is proposed for this alternative.
Amount Destroyed or Treated
None
Degree of Expected Reductions
in Toxicity, Mobility or Volume
through Treatment
No active treatment is proposed for this alternative, therefore, no reduction in
toxicity, mobility or volume through treatment will be achieved.
Degree to which Treatment is
Irreversible
No treatment is proposed.
Type and Quantity of Residuals
Remaining after Treatment
Existing conditions will remain since no treatment is proposed.
Degree to Which Treatment
Reduces Principal Threats
No treatment is proposed.
GSA-1
-------
TABLE GSA-1
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table GSA-1: No Action
EVALUATION CRITERIA
DETAILED ANALYSIS
SHORT-TERM EFFECTIVENESS
Protection of Community During
Remedial Action
Not applicable since no remedial actions are included in this alternative.
Protection of Workers During
Remedial Action
Not applicable since no remedial actions are included in this alternative.
Environmental Impacts
Not applicable since no remedial actions are included in this alternative.
Time Until Remedial Action
Objectives are Achieved
No active remedial actions will be implemented to reduce concentrations in soil to
RAOs. Therefore, RAO's will not be achieved through this alternative.
IMPLEMENT ABILITY
Ability to Construct and Operate
the Technology
Not applicable since no remedial actions are included in this alternative.
Reliability of the Technology
Not applicable since no remedial actions are included in this alternative.
Ease of Undertaking Additional
Remedial Actions, if necessary
This alternative will not limit or interfere with the ability to implement or perform
future remedial actions.
Ability to Monitor Effectiveness
of Remedy
Not applicable since no remedial actions or monitoring are included in this
alternative.
Ability to Obtain Approvals and
Coordinate with Other Agencies
Not applicable since no remedial actions are included in this alternative; therefore,
no approvals or coordination required.
Availability of off-site
Treatment, Storage and Disposal Not applicable for this alternative.
Services and Capacity
Availability of Necessary
Equipment and Specialists
No equipment or specialists required for this alternative.
Availability of Technology
Not applicable since no remedial technologies will be used.
COSTS - net present value (7%)
Capital Costs
$0
Annual Operation, Maintenance
and Monitoring
$40,000
Periodic Costs
$10,000
TOTAL
$50,000
GSA-1
-------
TABLE GSA-2
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table GSA-2: Excavation with Treatment and/or Disposal of Soil
EVALUATION CRITERIA
DETAILED ANALYSIS
OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT .
The results of the human health risk assessment indicated that select metals and
PAHs in soils may pose a potential future risk to site residents, facility workers
and/or construction workers.
Human Health Protection
Under this alternative, excavation of the impacted soil will be conducted to reduce
concentrations to meet cleanup goals, therefore the potential future risk to site
residents, facility workers and construction workers will be eliminated and RAOs
will be achieved.
The results of the ecological risk assessment indicated that current and potential
future risks to ecological receptors are present in soil in the GSA.
Ecological Protection
Under this alternative, excavation of the impacted soil will be conducted to reduce
concentrations to meet cleanup goals, therefore the potential future risk to
ecological receptors will be eliminated and RAOs will be achieved.
COMPLIANCE WITH ARARs
Chemical Specific
Under existing conditions, constituents in soil exceed chemical specific ARARs.
This alternative, will be designed and implemented to comply with the chemical
specific ARARs.
Location Specific
Location specific ARARs do not apply for this alternative since there are no
remedial activities associated with this alternative that will cause adverse impacts
to natural resources.
Action Specific
Action specific ARARs for this alternative are presented in Table E-3 in Appendix
E; this alternative will be designed and implemented to comply with applicable
action-specific ARARs.
LONG-TERM EFFECTIVENESS AND PERMANENCE
Magnitude of Residual Risk
Removal of the impacted material through excavation will significantly reduce any
residual risk.
Adequacy and Reliability of
Controls
Excavation of impacted soil will provide long-term effectiveness and permanence
since the material will be removed from the GSA and disposed of beneath the
landfill Final cover system. Post excavation confirmatory soil samples will be
collected to document the reliability of the alternative.
REDUCTION OF TOXICITY, MOBILITY AND VOLUME THROUGH TREATMENT
Treatment Process Used and
Materials Treated
Treatment of the excavated soil may or may not be required prior to disposal;
depending on the waste characterization results of the material being excavated, ex
situ treatment of soil may be implemented prior to disposal.
Amount Destroyed or Treated
Treatment of a portion of the excavated soil may be required prior to disposal;
however, the volume or concentrations will be dependent on waste characterization
analysis.
Degree of Expected Reductions
in Toxicity, Mobility or Volume
through Treatment
No active treatment of the excavated material is anticipated for this alternative;
however, through re-use/disposal of the material beneath a landfill cap, the toxicity,
mobility and volume of impacted material in the GSA is significantly reduced.
Degree to which Treatment is
Irreversible
No treatment is anticipated wilh this alternative.
GSA-2
-------
TABLE GSA-2
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table GSA-2; Excavation with Treatment and/or Disposal of Soil
EVALUATION CRITERIA
DETAILED ANALYSIS
Type and Quantity of Residuals
Remaining after Treatment
No active treatment of the excavated material is anticipated for this alternative.
Degree to Which Treatment
Reduces Principal Threats
No active treatment of the excavated material is anticipated for this alternative;
however, through excavation of the impacted material, the principal threats will be
eliminated.
SHORT-TERM EFFECTIVENESS ,
This alternative will not have significant short-term effects on the local community.
Protection of Community During Re-use/disposal of the material on-site is anticipated beneath the landfill final cover
Remedial Action system; however, should off-site treatment be required, local truck/vehicular traffic
will increase during implementation.
Protection of Workers During
Remedial Action
Work will be performed in accordance with applicable OSHA standards. Site-
specific health and safety plan(s) will be developed to protect site workers.
Environmental Impacts
Limited environmental impacts are anticipated.
Time Until Remedial Action
Objectives are Achieved
RAOs will be achieved upon removal of the impacted soil (1 to 2 years);
confirmatory soil sampling will be performed to document the achievement of
RAOs.
IMPLEMENTABILITY
Ability to Construct and Operate
the Technology
Soil excavation involves common techniques that arc straight forward to
implement.
Reliability of the Technology
Excavation of impacted soil is a reliable technology to quickly and effectively
control exposure risks.
Ease of Undertaking Additional
Remedial Actions, if necessary
This alternative will not limit or interfere with the ability to implement or perform
future remedial actions.
Ability to Monitor Effectiveness
of Remedy
Confirmatory soil sampling and analysis is easily implementable to measure the
effectiveness of the remedy.
Ability to Obtain Approvals and
Coordinate with Other Agencies
The remedial action will be designed and implemented under coordination with
appropriate Federal and State agencies.
Availability of off-site
Treatment, Storage and Disposal
Services and Capacity
Facilities are available to treat or dispose of the excavated material within the
northeast. However, it is assumed that excavated soil will be reused on-site at one
of the landfill lobes beneath the final cover system.
Availability of Necessary
Equipment and Specialists
Equipment, materials and services for this alternative are readily available.
Availability of Technology
Qualified engineers and contractors are readily available to design and implement
this alternative.
COSTS - net present value (7%)
Capital Costs
$184,000
Annual Operation, Maintenance
and Monitoring
$0
Periodic Costs
$16,000
TOTAL
$200,000
GSA-2
-------
TABLE DGGW-1
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table DGGW-T: No Action
EVALUATION CRITERIA
DETAILED ANALYSIS
OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT
Human Health Protection
The results of the human health risk assessment indicated the potential risk through
the potable use of site groundwater exists to future site residents and facility
workers.
Under this alternative, no remedial actions will be conducted to reduce residual
concentrations in downgradient groundwater to RAOs, Therefore the potential
future risk of potable groundwater use will remain and RAOs will not be achieved.
Ecological Protection
The results of the ecological risk assessment indicated no significant risks to
ecological receptors as a result of downgradient groundwater.
COMPLIANCE WITH ARARs -
Chemical Specific
Under existing conditions, concentrations of select compounds in downgradient
groundwater exceed chemical specific ARARs. No active treatment technologies
are implemented with this alternative; therefore, chemical specific ARARs will not
be met for this alternative.
Location Specific
Location specific ARARs do not apply for this alternative since there are no
remedial activities associated with this alternative that will cause adverse impacts to
natural resources.
Action Specific
Action specific ARARs do not apply for this alternative since there are no remedial
activities associated with this alternative.
LONG-TERM EFFECTIVENESS AND PERMANENCE
Magnitude of Residual Risk
Since there are no active remedial actions or institutional controls associated with
this alternative, potential future exposure to contaminants in groundwater witl
continue to pose a residual risk.
Adequacy and Reliability of
Controls
No controls are proposed for this alternative.
REDUCTION OF TOXICITY, MOBILITY AND VOLUME THROUGH TREATMENT
Treatment Process Used and
Materials Treated
No active treatment is proposed for this alternative.
Amount Destroyed or Treated
No active treatment is proposed for this alternative.
Degree of Expected Reductions
in Toxicity, Mobility or Volume
through Treatment
No reduction in toxicity, mobility or volume through treatment will be achieved
with this alternative.
Degree to which Treatment is
Irreversible
No active treatment is proposed.
Type and Quantity of Residuals
Remaining after Treatment
No active treatment is proposed.
Degree to Which Treatment
Reduces Principal Threats
No active treatment is proposed and therefore the potential risks of groundwater
consumption still remain.
SHORT-TERM EFFECTIVENESS
Protection of Community During
Remedial Action
Not applicable since no remedial actions are included in this alternative.
Protection of Workers During
Remedial Action
Not applicable since no remedial actions are included in this alternative.
DGGW-1
-------
TABLE DGGW-1
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table DGGW-T: No Action
EVALUATION CRITERIA
DETAILED ANALYSIS
Environmental Impacts
Not applicable since no remedial actions are included in this alternative.
Time Until Remedial Action
Objectives are Achieved
No active remedial actions will be implemented to reduce concentrations in
downgradient groundwater to PRGs, Therefore, RAOs will not be achieved
through this alternative.
IMPLEMENTABILITY
Ability to Construct and Operate
the Technology
Not applicable since no remedial actions are included in this alternative.
Reliability of the Technology
Not applicable since no remedial actions are included in this alternative.
Ease of Undertaking Additional
Remedial Actions, if necessary
This alternative will not limit or interfere with the ability to implement or perform
future remedial actions.
Ability to Monitor Effectiveness
of Remedy
Not applicable since no remedial actions or monitoring are included in this
alternative.
Ability to Obtain Approvals and
Coordinate with Other Agencies
Not applicable since no remedial actions are included in this alternative; therefore,
no approvals or coordination required.
Availability of off-site
Treatment, Storage and Disposal
Services and Capacity
Not applicable for this alternative,
Availability of Necessary
Equipment and Specialists
No equipment or specialists required for this alternative.
Availability of Technology
Not applicable since no remedial technologies will be used.
COSTS - net present value (7%)
Capital Costs
$0
Annual Operafion, Maintenance
and Monitoring
$41,000
Periodic Costs
$43,000
TOTAL
$84,000
DGGW-1
-------
TABLE DGGW-2
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table DGGW-2: In-situ Remediation
EVALUATION CRITERIA
DETAILED ANALYSIS
OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT
The results of the human health risk assessment indicated the potential risk through
the potable use of site groundwater exists to future site residents and facility
workers.
Human Health Protection
Under this alternative, in-situ natural attenuation mechanisms will be monitored to
address impacted groundwater following a phased approach to the groundwater
remedy. Until the RAOs are achieved, institutional controls will be in place to
prevent groundwater use/exposure, controlling human risks.
Ecological Protection
The results of the ecological risk assessment indicated no significant risks to
ecological receptors as a result of downgradient groundwater.
COMPLIANCE WITH AO ARs .•
Chemical Specific
Under existing conditions, concentrations of select compounds in groundwater
exceed chemical specific ARARs. Implementation of this alternative will be
expected to reduce contaminant concentrations in downgradient groundwater and
over time, achieve chemical-specific ARARs.
Location Specific
Potential location specific ARARs for this alternative are presented in Table E-4 in
Appendix E; this alternative provides the least amount of disruption to ecological
receptors and the wetland resource area during implementation. In-situ remedial
activities can be implemented to comply with applicable location-specific ARARs.
Action Specific
Potential action specific ARARs for this alternative are presented in Table E-4 in
Appendix E. In-situ remedial activities can be implemented to comply with
applicable action-specific ARARs.
LONG-TERM EFFECTIVENESS AND PERMANENCE
Magnitude of Residual Risk
Until the achievement of site RAOs, implementation of institutional controls will
reduce potential use and exposure to impacted groundwater. Therefore, residual
risk is low.
Adequacy and Reliability of
Controls
Assuming effective implementation and enforcement, institutional controls should
effectively limit human exposure to impacted groundwater until the RAOs are
achieved,
REDUCTION OF TOXICITY, MOBILITY AND VOLUME THROUGH TREATMENT
Treatment Process Used and
Materials Treated
Natural attenuation processes, including biodegradation, dispersion, dilution,
adsorption, volatilization and/or chemical and biological stabilization or destruction
of contaminants, will address groundwater COPCs in situ.
Amount Destroyed or Treated
Natural attenuation processes are anticipated to reduce the contaminants over time;
current dissolved concentrations indicate an estimated 200 lbs of VOCs in
downgradient groundwater.
Degree of Expected Reductions
in Toxicity, Mobility or Volume
through Treatment
Alternative does not include active treatment technologies. The degree to which
this alternative will reduce the toxicity, mobility and volume of contaminants
through natural attenuation is moderate, compared to other alternatives evaluated.
Degree to which Treatment is
Irreversible
Alternative does not include active treatment technologies. Natural attenuation
mechanisms are permanent.
DGGW-2
-------
TABLE DGGW-2
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table DGGW-2: In-situ Remediation
EVALUATION CRITERIA
DETAILED ANALYSIS
Type and Quantity of Residuals
Remaining after Treatment
No residuals will remain through in-situ natural attenuation processes.
Degree to Which Treatment
Reduces Principal Threats
The principal threats/exposure risks from groundwater will be controlled/reduced
through natural attenuation and institutional controls.
SHORT-TERM EFFECTIVENESS : '
Protection of Community During
Remedial Action
No impacts to the community are anticipated for this alternative.
Protection of Workers During
Remedial Action
Work will be performed in accordance with applicable OSHA standards. Site-
specific health and safety plan(s) will be developed to protect site workers.
Environmental Impacts
Impacts to the wetland resource areas are anticipated to be limited during
monitoring activities.
Time Until Remedial Action
Objectives are Achieved
RAOs will be achieved through natural attenuation processes; estimated timeframe
of
With Source Control - 67 to 79 years
Without Source Control - 81 to 98 years
IMPLEMENT ABILITY
Ability to Construct and Operate No construction activities are planned for this alternative other than installation of
the Technology additional monitoring wells; monitoring activities are easily implementable.
Reliability of the Technology
Site characterization data indicate that natural attenuation processes are effectively
degrading contaminants. Refer to Section 7.2 in the FS text for MNA discussion.
Ease of Undertaking Additional
Remedial Actions, if necessary
This alternative will not limit or interfere with the ability to implement or perform
future remedial actions.
Ability to Monitor Effectiveness
of Remedy
Groundwater sampling and analysis to evaluate contaminant levels is easily
implementable.
Ability to Obtain Approvals and
Coordinate with Other Agencies
The remedial action will be designed and implemented under coordination with
appropriate Federal and State agencies.
Availability of off-site
Treatment, Storage and Disposal
Services and Capacity
Not applicable for this alternative.
Availability of Necessary
Equipment and Specialists
Equipment, materials and services for this alternative are readily available.
Availability of Technology
Qualified engineers and contractors are available to design and implement this
alternative.
COSTS - nef present value (7%)
Capital Costs
$230,000
Annual Operation, Maintenance
and Monitoring
$1,400,000
Periodic Costs
$120,000
TOTAL
$1,750,000'
DGGW-2
-------
TABLE DGGW-3
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Fable DGGW-3: Hydraulic Containment through Groundwater Extraction, Treatment and Discharge
EVALUATION CRITERIA
DETAILED ANALYSIS
OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT
Human Health Protection
The results of the human health risk assessment indicated the potential risk through the potable
use of site groundwater exists to future site residents and facility workers,
Under this alternative, hydraulic containment of impacted groundwater through groundwater
extraction and ex-situ treatment will be implemented to control plume migration and meet
RAOs over time. Until the RAOs are achieved, institutional controls will be in place to
prevent groundwater use/exposure, controlling human risks,
Ecological Protection
The results of the ecological risk assessment indicated no significant risks to ecological
receptors as a result of downgradient groundwater.
COMPLIANCE WITH ARARs
Chemical Specific
Under existing conditions, concentrations of select compounds in groundwater exceed
chemical specific ARARs. Implementation of this alternative will be expected to reduce
contaminant concentrations in downgradient groundwater and over time, achieve chemical-
specific ARARs.
Location Specific
Potential location specific ARARs for this alternative are presented in Table F.-4 in Appendix
E; this alternative will provide disruption to ecological receptors and the wetland resource area
during implementation; however, the design, construction and operation of this alternative can
be implemented to comply with applicable location-specific ARARs,
Action Specific
Potential action specific ARARs for this alternative are presented in Table E-4 in Appendix E;
the design, construction and operation of this alternative can be implemented to comply with
applicable action-specific ARARs.
LONG-TERM EFFECTIVENESS AND PERMANENCE
Magnitude of Residual Risk
Until the achievement of site RAOs implementation of institutional controls will reduce
potential use and exposure to impacted groundwater. Therefore, residual risk is low.
Adequacy and Reliability of
Controls
Assuming effective implementation and enforcement, institutional controls should effectively
limit human exposure to impacted groundwater until the RAOs arc achieved. Monitoring of
the extraction system's effectiveness in hydraulicallv containing the plume will be required to
measure the reliability of the alternative. Extraction and treatment system components will
require maintenance, upkeep and potentially replacement overtime to ensure reliability.
REDUCTION OF TOXICITY, MOBILITY AND VOLUME THROUGH TREATMENT
Treatment Process Used and
Materials Treated
Materials treated within groundwater through the hydraulic containment extraction and ex-situ
treatment system will include VOCs, SVOCs & metals via a combination of technologies such
as air stripping, advanced oxidation processes and/or metals treatment, in addition to one or
more pretreatment steps (to be determined during remedial design phase).
An estimated total extraction rate of 75 gpm of groundwater will be treated through the
hydraulic containment groundwater extraction and ex-situ treatment system. Current dissolved
Amount Destroyed or Treated concentrations indicate an estimated 200 lbs of VOCs in downgradient groundwater available
for treatment,
DGGW-3
-------
TABLE DGGW-3
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
fable DGGW-3: Hydraulic Containment through Groundwater Extraction, Treatment and Discharge
EVALUATION CRITERIA
DETAILED ANALYSIS
Degree of Expected Reductions
in Toxicity, Mobility or Volume
through Treatment
The degree to which this alternative will reduce the toxicity and mobility of contaminants is
high and the degree to which it will reduce the volume of contaminants is moderate, compared
to other DGGW alternatives evaluated.
Degree to which Treatment is
Irreversible
Treatment of groundwater will be permanent.
Type and Quantity of Residuals
Remaining after Treatment
Treatment of the groundwater plume and any resulting VOC vapors will produce a moderate
volume of treatment residuals that may require off-site treatment/disposal at a licensed facility.
Degree to Which Treatment
Reduces Principal Threats
In conjunction with institutional controls, upon treatment of contaminants in groundwater, the
potential human risks to on-site downgradient groundwater will be eliminated.
SHORT-TERM EFFECTIVENESS
Protection of Community During
Remedial Action
Construction and operation of an on-site groundwater treatment facility will not have
significant short-term impacts on the local community; however, there may be a slight increase
in vehicular traffic to ihe site during construction activities.
Protection of Workers During
Remedial Action
Work will be performed in accordance with applicable OS HA standards. Site-specific health
and safety plan(s) will be developed to protect site workers.
Environmental Impacts
Impacts to the wetland resource areas are anticipated to be moderate to high during
construction activities due to the location of the extraction wells within the resource area
(requiring destruction of wetlands to install - estimated at 5,050 sq ft). Once the system is
installed, operation and monitoring activities is anticipated to have limited impacts. Available
practical means such as erosion and stormwater control measures will also be implemented to
minimize harm to wetland areas during construction.
Time Until Remedial Action
Objectives are Achieved
The estimated time to achieve groundwater RAOs is approximately
With Source Control - 57 to 68 years
Without Source Control - 70 to 86 years
IMPLEMENTABILITY
Ability to Construct and Operate
the Technology
The installation of wells and piping involves common construction techniques; however due to
the location of the impacted groundwater within the wetland resource area, this alternative
poses difficulty in implementation to reduce environmental impacts and in designing the
treatment system layout (access roads to extraction wells, burial of extraction and electrical
lines, etc.). Prior to implementation, pre-design pilot studies will be required to evaluate
groundwater capture zones.
Reliability of the Technology
Groundwater extraction is a demonstrated and reliable method for capturing and collecting
impacted groundwater. In addition, the ex-situ treatment components are effective in treating
groundwater to the remedial goals.
Ease of Undertaking Additional
Remedial Actions, if necessary
This alternative will not limit or interfere with the ability to implement or perform future
remedial actions.
Groundwater monitoring to demonstrate hydraulic containment and to determine contaminant
Ability to Monitor Effectiveness 'eve's>s easily implementable. Treatment system effluent will be monitored on a routine basis
of Remedy t0 eva'uate the effectiveness of the treatment system and document that discharge requirements
are being met.
Ability to Obtain Approvals and
Coordinate with Other Agencies
The remedial action will be designed and implemented under coordination with appropriate
Federal and State agencies. '
DGGW-3
-------
TABLE DGGW-3
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
fable DGGW-3: Hydraulic Containment through Groundwater Extraction, Treatment and Discharge
EVALUATION CRITERIA
DETAILED ANALYSIS
Availability of off-site.
Discharge of the treated groundwater will be to surface water or the local POTW,
Treatment. Storage and Disposal
Services and Capacity
Availability of Necessary
Equipment, materials and services for this alternative are readily available.
Equipment and Specialists
Availability of Technology
Qualified engineers and contractors are available to design and implement this alternative.
COSTS - net present value (7%)
Capital Costs
$2,900,000
Annual Operation, Maintenance
and Monitoring
$6,800,000 to $9,800,000
Periodic Costs
$130,000
TOTAL
$9,830,000 to $12,830,000
DGGW-3 O&M Range incorporates: 30 years of system operation with 30 years of groundwater monitoring - tow:
discharge to surface water, high: discharge to POTW
DGGW-3
-------
TABLE DGGW-4
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table DGGW-4: Groundwater Extraction and Ex-situ Treatment for Area-wide Contaminant
Reduction
EVALUATION CRITERIA
DETAILED ANALYSIS
OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT
The results of the human health risk assessment indicated the potential risk through the potable
use of site groundwater exists to future site residents and facility workers.
Human Health Protection
Under this alternative, groundwater extraction and ex-situ treatment for area-wide contaminant
reduction will be implemented to control plume migration and aggressively treat groundwater
to meet RAOs in an expedited timeframe. Until the RAOs are achieved, institutional controls
will be in place to prevent groundwater use/exposure, controlling human risks.
Ecological Protection
The results of the ecological risk assessment indicated no significant risks to ecological
receptors as a result of downgradient groundwater.
COMPLIANCE WITH ARARs ,
Chemical Specific
Under existing conditions, concentrations of select compounds in groundwater exceed
chemical specific ARARs. Implementation of this alternative will be expected to reduce
contaminant concentrations in downgradient groundwater and over time, achieve chemical-
specific ARARs.
Location Specific
Potential location specific ARARs for this alternative are presented in Table E-4 in Appendix
E; this alternative will provide significant disruption to ecological receptors and the wetland
resource area during implementation. However, the design, construction and operation of this
alternative can be implemented to comply with applicable location-specific ARARs.
Action Specific
Potential action specific ARARs for this alternative are-presented in Table E-4 in Appendix E;
the design, construction and operation of this alternative can be implemented to comply with
applicable action-specific ARARs,
LONG-TERM EFFECTIVENESS AND PERMANENCE
Magnitude of Residual Risk
Until the achievement of site RAOs implementation of institutional controls will reduce
potential use and exposure to impacted groundwater. Therefore, residual risk is low.
Adequacy and Reliability of
Controls
Assuming effective implementation and enforcement, institutional controls should effectively
limit human exposure to impacted groundwater until the RAOs are achieved. The
groundwater treatment system will adequately and reliably reduce the concentrations in
downgradient groundwater. Extraction and treatment system components will require
maintenance, upkeep and potentially replacement overtime to ensure reliability over time.
REDUCTION OF TOXICITY, MOBILITY AND VOLUME THROUGMlISSSMENl' <
Treatment Process Used and
Materials Treated
Materials treated within groundwater through the hydraulic containment extraction and ex-situ
treatment system will include VOCs, SVOCs & metals via a combination of technologies such
as air stripping, advanced oxidation processes and/or metals treatment, in addition to one or
more pretreatment steps (to be determined during remedial design phase).
Amount Destroyed or Treated
An estimated total extraction rate of 140 gpm of groundwater will be treated through the
groundwater extraction and ex-situ treatment system. Current dissolved concentrations
indicate an estimated 200 lbs of VOCs in downgradient groundwater available for treatment.
DGGW-4
-------
TABLE DGGW-4
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table DGGW-4: Groundwater Extraction and Ex-situ Treatment for Area-wide Contaminant
Reduction
EVALUATION CRITERIA
DETAILED ANALYSIS
Degree of Expected Reductions
in Toxicity, Mobility or Volume
through Treatment
Compared to other alternatives evaluated for downgradient groundwater, this alternative
provides a high level of reduction in toxicity, mobility and volume of contaminants through ex
situ treatment.
Degree to which Treatment is
Irreversible
Treatment of groundwater will be permanent.
Type and Quantity of Residuals
Remaining after Treatment
Treatment of the groundwater plume and any resulting VOC vapors may produce a high
volume of treatment residuals that will require off-site treatment/disposal at a licensed facility.
Degree to Which Treatment
Reduces Principal Threats
In conjunction with institutional controls, upon treatment of contaminants in groundwater, the
potential human risks to on-site downgradient groundwater will be eliminated.
SHORT-TERM EFFECTIVENESS
Protection of Community During
Remedial Action
Construction and operation of an on-site groundwater treatment facility will not have
significant short-term impacts on the local community; however, there may be a slight increase
in vehicular traffic to the site during construction activities.
Protection of Workers During
Remedial Action
Work will be performed in accordance with applicable OSHA standards. Site-specific health
and safety plan(s) will be developed to protect site workers.
Environmental Impacts
Impacts to the wetland resource areas are anticipated to be high during construction activities
due to the location of the extraction wells within the resource area (requiring destruction of
almost an acre of wetlands to install). Once the system is installed, operation and monitoring
activities are anticipated to have limited to no impacts. Available practical means such as
erosion and stormwater control measures will also be implemented to minimize harm to
wetland areas during construction.
Time Until Remedial Action
Objectives are Achieved
The estimated time to achieve groundwater RAOs is approximately
With Source Control - 40 to 49 years
Without Source Control - 53 to 66 years
IM PLEM ENT ABILITY
Ability to Construct and Operate
the Technology
The installation of wells and piping involves common construction techniques; however due to
the location of the impacted groundwater within the wetland resource area, this alternative
poses difficulty in implementation to reduce environmental impacts and in designing the
treatment system layout (access roads to extraction wells, burial of extraction and electrical
lines, etc.). Prior to implementation, pre-design pilot studies will be required to evaluate
adequate groundwater capture zones.
Reliability of the Technology
Groundwater extraction is a demonstrated and reliable method for capturing and collecting
impacted groundwater. In addition, the ex-situ treatment components are effective in treating
groundwater to the remedial goals.
Ease of Undertaking Additional
Remedial Actions, if necessary
This alternative will not limit or interfere with the ability to implement or perform future
remedial actions.
Groundwater monitoring to demonstrate hydraulic containment and to determine contaminant
Ability to Monitor Effectiveness levels is easily implementable. Treatment system effluent will be monitored on a routine basis
of Remedy to evaluate the effectiveness of the treatment system and document that discharge requirements
are being met.
Ability to Obtain Approvals and
Coordinate with Other Agencies
The remedial action will be designed and implemented under coordination with appropriate
Federal and State agencies.
DGGW-4
-------
TABLE DGGW-4
DETAILED ANALYSIS OF REMEDIAL ALTERNATIVE
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table DGGW-4: Groundwater Extraction and Ex-situ Treatment for Area-wide Contaminant
Reduction
EVALUATION CRITERIA
DETAILED ANALYSIS
Availability of off-site
Discharge of the treated groundwater will be to surface water or the local POTW.
Treatment, Storage and Disposal
Services and Capacity
Availability of Necessary
Equipment and Specialists
Equipment, materials and services for this alternative are readily available.
Availability of Technology
Qualified engineers and contractors are available to design and implement this alternative.
COSTS - net present value (7%)
Capital Costs
$4,500,000
Annual Operation, Maintenance
and Monitoring
$6,500,000 to $12,200,000
Periodic Costs
$130,000
TOTAL
$11,130,000 to $16,830,000
DGGW-4 OSM Range incorporates: Low - 30 years of system operation (discharge to surface water) with 30 years
of groundwater monitoring and High: 30 years of system operation (discharge to POTW) with 30 years of
groundwater monitoring
DGGW-4
-------
TABLE K-1
COMPARATIVE ANALYSIS FOR THE LANDFILL LOBE REMEDIAL ALTERNATIVES
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
EVALUATION CRITERIA
LF-t
LF-2a and LF-2b
LF-3
LF-4
Human Health Protection
The potential human health risks will remain and
RAOs will not be achieved.
The potential human health risks win be eliminated
and RAOs will be achieved.
The potential human health risks will be eliminated
and RAOs will be achieved.
The potential human health risks will be eliminated
and RAOs will be achieved.
Ecological Protection
The potential future risk to ecological receptors will
remain and RAOs will not be achieved.
The potential future risk to ecological receptors will be
eliminated and RAOs will be achieved.
The potential future risk to ecological receptors will be
eliminated and RAOs will be achieved.
The potential future risk to ecological receptors will be
eliminated and RAOs will be achieved.
Chemical Specific
Chemical specific ARARs will not be met for this
alternative in a timely manner.
This alternative will meet the RAOs and therefore
comply with the chemical specific ARARs.
This alternative will meet the RAOs and therefore
comply with the chemical specific ARARs.
This alternative will meet the RAOs and therefore
comply with the chemical specific ARARs.
Location Specific
Location specific ARARs do not apply for this
alternative.
This alternative will be designed and implemented to
comply with applicable location-spec jpc ARARs.
This alternative will be designed and implemented to
comply with applicable location-specific ARARs.
This alternative may not meet applicable location-
specific ARARs, specific to the amount of work in the
wetland resource areas.
Action Specific
Action specific ARARs do not apply for this
alternative.
This alternative will be designed and implemented to
comply with applicable action-specific ARARs.
This alternative will be designed and implemented to
comply with applicable action-specific ARARs.
This alternative will be designed and implemented to
comply with applicable action-specific ARARs.
¦- -.. . 1 ONR-TFRM FFFFCTlVf^FRC; ANI") PFRMANFNC.F- fSv.r"
Magnitude of Residual Risk
Potential future exposure to contaminants in waste,
sediment, surface water and groundwater will continue
to pose a potential residual risk.
Residual risk is low; comparable to LF-3 and LF-4,
Residual risk is low; comparable to LF-2 and LF-4.
Residual risk is low, comparable to LF-2 and LF-3.
Adequacy and Reliability of
Controls
No controls proposed.
LF-2 prevents exposure to the waste, reduces
infiltration through the waste into groundwater,
prevents or reduces the potential for re-contamination
of the brook, and limits human exposure to impacted
groundwater until groundwater RAOs are achieved.
Containment of groundwater utilizing i vertical barrier
(in conjunction with monitored natural attenuation (LF-
2a) or active groundwater treatment (LF-2b)) is
anticipated to effectively and reliably limit human
exposure to impacted groundwater until RAOs are met.
LF-3 prevents exposure to the waste, reduces
infiltration through the waste into groundwater,
prevents or reduces the potential for re-contamination
of the brook, and limits human exposure to impacted
groundwater until groundwater RAOs are achieved.
Collection of groundwater with ex-situ treatment is
anticipated to effectively and reliably limit human
exposure to impacted groundwater until RAOs are met.
LF-4 prevents exposure to the waste, reduces
infiltration through the waste into groundwater,
prevents or reduces the potential for re-contamination
of the brook, and limits human exposure to impacted
groundwater until groundwater RAOs are achieved-
Containment of groundwater utilizing a vertical barrier
(in conjunction with active groundwater treatment) is
anticipated to effectively and reliably limit human
exposure to impacted groundwater until RAOs are met.
RFDUCTiON r>F TOXICITY; MnfiiriimND ^ v
Treatment Process Used and
Materials Treated
No active treatment is proposed.
Materials addressed in groundwater include VOCs,
SVOCs & metals. Alternative LF-2a does not actively
treat groundwater, MNA processes will address COCs
in-situ following a phased approach to the groundwater
remedy. Alternative LF-2b will treat these COCs in-
situ (e.g., chemical oxidation) or if extraction and ex-
situ treatment is implemented, a combination of
technologies such as air stripping, advanced oxidation
processes and/or metals treatment, in addition to one
or more pretreatment steps (to be determined during
the design phase) will be used.
Materials treated in groundwater include VOCs,
S VOCs & metals; a combination of technologies such
as air stripping, advanced oxidation processes and/or
metals treatment, in addition to one or more
pretreatment steps (to be determined during the design
phase) will be utilized to treat the COCs extracted.
Same as LF-2b.
Amount Destroyed or Treated
None
Current dissolved concentrations indicate an estimated
2,700 to 4,500 ibs of VOCs in Northern and Southern
lobe groundwater.
Same as LF-2 and LF-4.
Same as LF-2b and LF-3.
K-1
-------
TABLE K-1
COMPARATIVE ANALYSIS FOR THE LANDFILL LOBE REMEDIAL ALTERNATIVES
Remedial Investigation and Feasibility Study
MA
EVALUATION CRITERIA
LF-1
LF-2a and LF-2b
LF-3
LF-4
Degree of Expected Reductions
in Toxicity, Mobility or Volume
through Treatment
No reduction in toxicity, mobility or volume through
treatment will be achieved.
Compared to other alternatives evaluated for the
landfill lobes, this alternative provides a low (LF-2a)
to moderate (LF-2b) level of reduction in toxicity,
mobility and volume of contaminants through
treatment.
Compared to other alternatives evaluated Cor the
landfill lobes, this alternative provides, through
groundwater treatment, a moderate level of reduction
in toxicity and volume and a high level of reduction
with regard to mobility of contaminants.
Same as LF-2b.
Degree to which Treatment is
Irreversible
No treatment is proposed.
Alternative LF-2a does not include treatment
technologies. Under Alternative LF-2b. the
groundwater treatment will be permanent.
Same as LF-2b and LF-4,
Same as LF-2b and LF-3.
Type and Quantity of Residuals
Remaining after Treatment
Existing conditions will remain since no treatment is
proposed.
MNA process will address COCs in-situ. Low volume
of residuals anticipated following groundwater
treatment (LF-2b).
Moderate to high volume of residuals anticipated
following groundwater treatment.
Same as LF 2 b.
Degree to Which Treatment
Reduces Principal Threats
No treatment is proposed.
Overall, this alternative presents a high degree of
reducing principal threats since in-situ natural
attenuation process with or without enhancements (LF-
2a) or active treatment (LF-2b) will address
groundwater impacts and in conjunction with the
physical barrier, will prevent re-cont^piinntion of the
brook.
Overall, this alternative presents a high degree of
reducing principal threats through treatment since it
extracts and treats a large volume of impacted
groundwater.
Same as LF-2b.
If it in iwniMi in ii Fiiiiiiiniiii ii i ii iiiaiiiiiii' v, ¦- "Vj"-"
Protection of Community During
Remedial Action
Not applicable.
Limited short-term effects anticipated.
Moderate short-term effects anticipated; slight
increase over LF-2 due to longer construction
timeframe (for groundwater components).
Higher short-term effects anticipated due to the
lengthier construction timeframe (re-routing brook and
wetlands replication).
Protection of Workers During
Remedial Action
Not applicable.
Work will be performed in accordance with applicable
OSHA standards. Site-specific health and safety
plan(s) will be developed to protect site workers.
Same as LF-2 and LF-4.
Same as LF-2 and LF-3.
Environmental Impacts
Not applicable.
Impacts to the wetland resource areas are anticipated
to be moderate during construction activities due to
the location of the wetland resource areas surrounding
the landfill lobes and during the brook excavation,
temporary re-directing/routing of the brook may be
required to effectively remove the impacted sediment,
potentially causing disruption to the existing
ecological habitat.
Similar to LF-2, with a slightly higher area of impact
due to the groundwater component.
Impacts to the wetland resource areas are anticipated
to be high during construction activities due to the
destruction of the existing wetland/marsh area to the
south of the southern lobe during the brook re-creation
(disrupting ecological habitat) and due to the location
of the wedand resource areas surrounding the landfill
lobes (erosion controls and stormwater management
will be required to reduce impacts).
Time Until Remedial Action
Objectives are Achieved
RAO's will not be achieved through this alternative.
65 to 210 years
52 to 164 years
65 to 210 years
implementability - -
Ability to Construct and Operate
the Technology
Not applicable.
This alternative involves common construction
techniques; however the presence of wetland resource
areas and the adjacent 100-year flood plain may
present potential design challenges. This alternative
provides a reduced level of operation, maintenance
and monitoring than LF-3.
This alternative involves common construction
techniques; however the presence of wetland resource
areas and the adjacent 100-year flood plain may
present potential design challenges. This alternative
provides a higher level of operation, maintenance and
monitoring than other alternatives evaluated (e.g. LF-2
and LF-4).
In general, this alternative involves common
construction techniques; however the presence of
wetland resource areas and the 100-year flood plain
will present potential design challenges. In addition,
implementation/construction of re-routing the brook
will present access and habitat disruption issues.
K-1
-------
TABLE K-1
COMPARATIVE ANALYSIS FOR THE LANDFILL LOBE REMEDIAL ALTERNATIVES
Remedial Investigation and Feasibility Study
EVALUATION CRITERIA
LF-1
LF-2a and LF-2b
LF-3
LF-4
Reliability of the Technology
Not applicable.
'if
The combination of technologies that,this alternative
incorporates presents a reliable approach to comply
with ARARs and achieve RAOs. §
'•1
!
Same as LI -2
The combination of technologies that this alternative
incorporates presents a reliable approach to achieve
RAOs; however due to the issues associated with re-
routing the brook (i.e. recreating function and value of
resource areas on-site and finding available space on-
site), this alternative is not as reliable as the other
alternatives to meet RAOs.
Ease of Undertaking Additional
Remedial Actions, if necessary
This alternative will not limit or interfere with the
ability to implement or perform future remedial
actions.
This alternative should not limit or ij|eifere with the
ability to implement or perform future remedial
actions. *
Similar to LF-2 and LF-4.
Similar to LF-2 and LF-3.
Ability to Monitor Effectiveness
of Remedy
Not applicable.
Confirmatory sediment sampling and analysis is easily
implementable to measure the effectiveness of the
brook sediment excavation. Groundwater monitoring
to demonstrate contaminant containment and mass
reduction is easily implementable.
Same as LF-2 and LF-4.
Same as LF-2 and LF-3.
Ability to Obtain Approvals and
Coordinate with Other Agencies
Not applicable since no remedial actions are included
in this alternative; therefore, no approvals or
coordination required.
The remedial action will be designed and implemented
under coordination with appropriate Federal and State
agencies.
Same as LF-2.
With the potential ARAR issues in regards to the
Massachusetts Wetlands Act, this alternative may have
difficulty obtaining approval (i.e., substantial
compliance).
Availability of off-site
Treatment, Storage and Disposal
Services and Capacity
Not applicable for this alternative.
Facilities are available to treat or dispose of the
excavated material within Massachusetts. However,
there is also availability to re-use this material on-site
at one of the landfill lobes beneath the final cover
system. If groundwater extraction and ex-situ
treatment are implemented, the treated groundwater
can be discharged to surface water or to the local
POTW.
Similar to LF-2 and LF-4.
Similar to LF-2 and LF-3.
Availability of Necessary
Equipment and Specialists
No equipment or specialists required for this
alternative.
Equipment, materials and services foe this alternative
are readily available.
Same as LF-2 and LF-4,
Similar to LF-2 and LF-3.
Availability of Technology
Not applicable since no remedial technologies will be
used.
Qualified engineers and contractors are available to
design and implement this alternative.
Same as LF-2 and LF-4.
Similar to LF-2 and LF-3.
, ,. ... ^coSTS - netpresSWvalue (7%) -30 vears
Capital Costs
$0
$17,500,000 LF-2a
to
$19,700,000 LF-2b
$24,900,000
$25,900,000
Annual Operation, Maintenance
and Monitoring
$68,000
$2,900,000 IF-2a
to
$5,400,000 LF-2b
$15,900,000
to
$26,100,000
$5,400,000
Periodic Costs
$43,000
$120,000
$130,000
$120,000
TOTAL
$111,000
$20,520,000 LF"2a
to
$25,220,000 LF-2b
$40,930,000
to
$51,130,000
$31,420,000
K-1
-------
TABLE K-2
COMPARATIVE ANALYSIS FOR THE FORMER DRUM DISPOSAL AREA REMEDIAL ALTERNATIVES
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
Table K-2
EVALUATION CRITERIA
FDDA-1
FDDA-2
FDDA-3
FDDA-4
FDDA-5
vmm- ¦ PROTECTION OF+IUMlfi HEALTH AND THE ENVIRONMENT ¦**'
Human Health Protection
The potential future risks will remain.
This alternative controls the potential future risks
threw eh containment.
This alternative eliminates the potential future risks.
This alternative eliminates the potential future risks.
This alternative eliminates the potential future risks.
Ecological Protection
The potential future risks will remain-
The potential future risks will be controlled through
containment.
The potential future risks will be eliminated.
The potential future risks will be eliminated.
The potential future risks will be eliminated.
,. ¦ /immm
mmmmmmmmmmim ..-eoMPUMWiwiTH arars:^ \
ife-r"
.
Chemical Specific
Chemical specific ARARs will not be met for this
alternative.
This alternative will prevent exposure to the impacted
material, but may not meet the RAOs in soil and
therefore may not comply with the chemical specific
ARARs in the foreseeable future.
This alternative will meet the RAOs over time and
therefore comply with the chemical specific ARARs.
This alternative will meet the RAOs over time and
therefore comply with the chemical specific ARARs.
This alternative will meet the RAOs over time and
therefore comply with the chemical specific ARARs.
Location Specific
Location specific ARARs do not apply for this
alternative.
This alternative will be designed and implemented to
comply with applicable location-specific ARARs.
This alternative will be designed and implemented to
comply s^th applicable location-specific ARARs.
This alternative will be designed and implemented to
comply with applicable location-specific ARARs.
This alternative will be designed and implemented to
comply with applicable location-specific ARARs.
Action Specific
Action specific ARARs do not apply for this
alternative.
This alternative will be designed and implemented to
comply with applicable action-specific ARARs.
This alternative will be designed and implemented to
comply with applicable action-specific ARARs.
This alternative will be designed and implemented to
comply with applicable action-specific ARARs.
This alternative will be designed and implemented to
comply with applicable action-specific ARARs.
-V 'Ml'.,-?.
-222S2^;^.^LONG-TERM EFFECTBMESS AND PERMANENCE ' —
vSr."", *" '
Magnitude of Residual Risk
Potential future exposure to contaminants in soil will
continue to pose a potential residual risk.
Hydraulic containment of impacted groundwater will
significantly reduce residual risk; however, the
impacted soil will remain (beneath the containment
barrier), providing the potential for future leaching into
groundwater over time. Therefore, residual risk is
relatively high, compared to FDDA-3 through FDDA-
5.
Hydraulic containment of impacted groundwater will
significantly reduce residual risk. In addition, removal
of the impacted soil through excavation will
significantly reduce any residua! risk associated with
the impacted soil. Therefore, residual risk is low
compared to FDDA-1 and FDDA-2 and comparable to
FDDA-5.
Removal of the impacted soil through excavation will
significantly reduce any residual risk associated with
the impacted soil. A phased groundwater remedial
action will further reduce residual risk over time.
Therefore, residual risk is low to moderate compared to
the other alternatives.
Similar to FDDA-3.
Adequacy and Reliability of
Controls
No controls proposed.
Institutional controls should effectively limit human
exposure to impacted soil and groundwater.
Monitoring of the extraction system's effectiveness in
hydraulically containing the plume will be required to
determine the reliability of the groundwater component
of this alternative and routine monitoring that the
containment barrier is intact will be required to
determine the reliability of the soil component of this
alternative. ,
Excavation of impacted soil will provide long-term
effectiveness and permanence since the material will be
removed. Institutional controls should effectively limit
human exposure to impacted groundwater until
groundwater RAOs are achieved. Monitoring of the
extraction system's effectiveness in hydraulically
containing the plume will be required to determine the
reliability pf the groundwater component of this
alternative
Excavation of impacted soil will provide long-term
effectiveness and permanence since the material will be
removed. Institutional controls should effectively limit
human exposure to impacted groundwater until
groundwater RAOs are achieved through natural
attenuation with or without enhancements. Monitoring
will be required to determine the reliability of the
groundwater component of this alternative.
Similar to FDDA-3.
' -:^^^©^s3^isj|>MHM^ION:ORTOXICITY1MOBllSmNDVC^UME^BOOeHTnEOTMEOT«^feSP¥^sW'i:^, ' SUB: '. ¦¦¦¦¦-- ¦ — V-
Treatment Process Used and
Materials Treated
No active treatment is proposed for this alternative.
Materials treated within groundwater include VOCs,
SVOCs and metals via a combination of technologies
such as air stripping, advanced oxidation processes
and/or metals treatment, in addition to one or more
pretreatment steps (to be determined during remedial
design phase).
¦J
1
*
Treatment of the excavated soil may or may not be
required prior to disposal; depending on the waste
characterization sampling results. Materials treated
within groundwater include VOCs, SVOCs and metals
via a combination of technologies such as air stripping,
advanced oxidation processes and/or metals treatment,
in addition to one or more pretreatment steps (to be
determined during remedial design phase).
Treatment of the excavated soil may or may not be
required prior to disposal; depending on the waste
characterization sampling results. Natural attenuation
processes, including biodegradation, dispersion,
dilution, adsorption, volatilization and/or chemical and
biological stabilization or destruction of contaminants,
will address impacted groundwater (VOCs. SVOCs
and metals). Following the phased approach, this
alternative may also include MNA enhancements, other
in-situ treatment components, or groundwater
extraction and treatment. If implemented, the in-situ or
ex-situ treatment system will treat groundwater via a
combination of technologies such as air stripping,
advanced oxidation processes and/or metals treatment,
in addition to one or more pretreatment steps (to be
determined during design phase).
Same as FDDA-3.
K-2
-------
TABLE K-2
COMPARATIVE ANALYSIS FOR THE FORMER DRUM DISPOSAL AREA REMEDIAL ALTERNATIVES
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
EVALUATION CRITERIA
FDDA-1
FDDA-2
FDDA-3
FDDA-4
FDDA-5
Amount Destroyed or Treated
None
No soil will be treated, but an estimated total extraction
rate of 20 gpm of groundwater will be treated through
the groundwater extraction and ex-situ treatment
system. Current dissolved concentrations indicate an
estimated 1,60G to 2,000 lbs of VOCs in FDDA
groundwater available for treatment. With the soil
remaining in-situ, the potential exists for future
leaching of additional contaminants from soil to
groundwater.
Treatment of a portion of the excavated soil may be
required prior to disposal; however, the volume or
concentrations will be dependent on waste
characterization analysts. An estimated total extraction
rate of 24 gpm of groundwater will be treated through
the groundwater extraction and ex-situ treatment
system. Current dissolved concentrations indicate an
estimated 1,600 to 2,000 lbs of VOCs in FDDA
groundwater available for treatment.
Treatment of a portion of the excavated soil may be
required prior to disposal; however, the volume or
concentrations will be dependent on waste
characterization analysis. Current dissolved
concentrations indicate an estimated 1.600 to 2,000 lbs
of VOCs in FDDA groundwater. Natural attenuation
processes with or without enhancements will address
the dissolved plume. Following the phased
groundwater approach, and in-situ treatment system or
a groundwater extraction and ex-situ treatment system
may be implemented (estimated total extraction rate of
15 gpm of groundwater).
Similar to FDDA-3, but with an anticipated extraction
rate of 50 gpm.
Degree of Expected Reductions
in Toxicity, Mobility or Volume
through Treatment
No active treatment is proposed for this alternative,
therefore, no reduction in toxicity, mobility or volume
through treatment will be achieved with this
alternative.
Compared to other alternatives evaluated for the
FDDA, this alternative provides a low level of
reduction in toxicity and volume of contaminants and a
high level of reduction in mobility of contaminants.
Compared 10 other alternatives evaluated for the
FDDA, this alternative provides a moderate level of
reduction in toxicity, mobility and volume of
contaminants through groundwater (and potentially
soil) treatment.
Compared to other alternatives evaluated for the
FDDA, this alternative provides a lower level of
reduction in toxicity, mobility and volume of
contaminants through groundwater (and potentially
soil) treatment.
Compared to other alternatives evaluated for the
FDDA, this alternative provides a moderate to high
level of reduction in toxicity, mobility and volume of
contaminants through groundwater (and potentially
soil) treatment.
Degree to which Treatment is
Irreversible
No treatment is proposed.
No soil will be actively treated, The groundwater
treatment will be permanent.
The groundwater and, if required, soil treatment will be
permanent
If required, the groundwater and soil treatment will be
permanent.
Same as FDDA-3,
Type and Quantity of Residuals
Remaining after Treatment
Existing conditions will remain since no treatment is
proposed.
Treatment of the groundwater plume and any resulting
VOC vapors will result in a low to moderate volume of
treatment residuals that will require off-site
treatment/disposal at a licensed facility.
Similar to FDDA-2.
Limited to no residuals remaining after treatment.
Slightly higher residuals than other alternatives
evaluated.
Degree to Which Treatment
Reduces Principal Threats
No treatment is proposed.
Principal threats of soil exposure and potential leaching
from soil to groundwater are not addressed via
treatment for this alternative; however, in conjunction
with institutional controls and construction of the
containment barrier, the treatment of contaminants in
groundwater will control the principal threats/ exposure
risks over time.
Principal thr eats of soil exposure and potential leaching
from soil to groundwater are not addressed via
treatment for this alternative; however, through
excavation, institutional controls, groundwater
extraction and treatment, the principal threats/ exposure
risks will be controlled over time.
Through excavation, institutional controls, and natural
attenuation process, the principal threats/exposure risks
will be controlled over time.
Similar to FDDA-3.
" r..::- •- - - SHORT-TERM£FFECTIVENESS ¦ • 3"'- '
Protection of Community During
Remedial Action
Not applicable.
Construction activities are not anticipated to have
significant short-term impacts on the local community;
however, there may be a slight increase in vehicular
traffic to the site during construction activities.
This alternative will not have significant short-term
effects on the local community. Re-use/disposal of the
material on-site is anticipated beneath the landfill final
cover system; however, should off-site treatment be
required, local truck/vehicular traffic may be increased
during implementation.
Similar to FDDA-3 and FDDA-5.
Similar to FDDA-3 and FDDA-4.
Protection of Workers During
Remedial Action
Not applicable.
Comparable to other alternatives; slightly reduced
exposure risk during implementation since soil remains
in-place.
Comparable to alternatives FDDA-4 and FDDA-S.
Comparable to alternatives FDDA-3 and FDDA-S,
Comparable to alternatives FDDA-3 and FDDA-4.
Environmental Impacts
Not applicable.
Impacts to the wetland resource areas are anticipated to
be moderate, compared to other alternatives evaluated.
Impacts to the wetland resource areas are anticipated to
be moderate, compared to other alternatives evaluated.
Impacts to the wetland resource areas are anticipated to
be low to moderate, compared to other alternatives
evaluated.
Impacts to the wetland resource areas are anticipated to
be moderate to high, compared to other alternatives
evaluated.
Time Until Remedial Action
Objectives are Achieved
RAO's will not be achieved through this alternative.
30 to 134 years
24 to 89 years
36 to 103 years
23 lo 85 years
K-2
-------
TABLE K-2
COMPARATIVE ANALYSIS FOR THE FORMER DRUM DISPOSAL AREA REMEDIAL ALTERNATIVES
Remedial investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
EVALUATION CRITERIA
FDDA-1
FDDA-2
FDDA-3
FDDA-4
FDDA-5
.IMRESJfiNTABILITy.-r--v.,Si&-r
Ability to Construct and Operate
the Technology
Not applicable.
Comparable to other alternatives; slightly higher
difficulty in construction of the soil barrier due to the
proximity of the resource area and in designing the
barrio- due lo the potential future use of the FDDA as a
Northern lobe stormwater management basin.
Comparable to other alternatives; slightly higher level
of disruption and difficulty constructing the
groundwater extraction system components within or
immediately adjacent to the wetland resource areas.
Comparable to other alternatives; less disruption and
difficulty constructing within or immediately adjacent
to the wetland resource areas.
Comparable to alternative FDDA-3, with a slightly
higher level of disruption due to the wetland resource
areas.
Reliability of the Technology
Not applicable.
Reduced reliability than FDDA-3 through FDD A-5
since source material remains in place.
Comparable to FDDA-4 and FDDA-5; higher
reliability than FDDA-1 and FDDA-2.
Comparable to FDDA-3 and FDDA-5; higher
reliability than FDDA-1 and FDDA-2.
Comparable to FDDA-3 and FDDA-4; higher
reliability than FDDA-1 and FDDA-2.
Ease of Undertaking Additional
Remedial Actions, if necessary
This alternative will not limit or interfere with the
ability to implement or perform future remedial actions.
Utilizing the area as a stormwater management basin
for the Northern lobe final cover system and leaving the
soil in place will present difficulty in undertaking
additional remedial actions due to access restrictions.
This alternative would not limit or interfere with the
ability to implement or perform future remedial actions;
same as FDDA-4 and FDDA-5.
Same as FDDA- 3 and FDDA-5.
Same as FDDA-3 and FDDA-4.
Ability to Monitor Effectiveness
of Remedy
Not applicable.
Groundwater monitoring to demonstrate contaminant
redaction is easily implementable. Treatment system
effluent will be monitored on a routine basis to evaluate
the effectiveness of the treatment system and document
that discharge requirements arc being met. Routine
inspection of the containment barrier is easily
implementable as well.
Confirmatory soil sampling and analysis is easily
implementable to measure the effectiveness of the soil
component of this alternative. Groundwater
monitoring to demonstrate contaminant reduction is
easily implementable. Treatment system effluent will
be monitored on a routine basis to evaluate the
effectiveness of the treatment system and document
that discharge requirements are being met.
Confirmatory soil sampling and analysis is easily
implementable to measure the effectiveness of the soil
component of this alternative. Groundwater
monitoring to demonstrate contaminant reduction is
easily implementable.
Same as FDDA-3.
Ability to Obtain Approvils and
Coordinate with Other Agencies
Not applicable.
The remedial action will be designed and implemented
under coordination with appropriate Federal and State
agencies.
Same as FDDA-2, FDDA-4 and FDDA-5.
Same as FDDA-2, FDDA-3 and FDDA-5.
Same as FDDA-2 through FDDA-4.
Availability of off-site Treatment,
Storage and Disposal Services
and Capacity
Not applicable.
No off-site treatment, storage or disposal services
required for the soil component of the alternative.
Discharge of the treated groundwater will be to surface
water or the local POTW.
Facilities are available to treat or dispose of the
excavated material within the northeast. However, it is
assumed that excavated soil will be reused on-site at
one of the landfill lobes beneath the final cover system.
Discharge of the treated groundwater will be to surface
water or the local POTW.
Facilities are available to treat or dispose of the
excavated material within the northeast. However, it is
assumed that excavated soil will be reused on-site at
one of the landfill lobes beneath the final cover system.
If groundwater extraction and ex-situ treatment is
implemented (through phased approach), discharge of
the treated groundwater will be to surface water or the
local POTW.
Same as FDDA-3.
Availability of Necessary
Equipment and Specialists
No equipment or specialists required for this
alternative.
Equipment, materials and services for this alternative
are readily available.
Same as FDDA-2, FDDA-4 and FDDA-5.
Same as FDDA-2, FDDA-3 and FDDA-5.
Same as FDDA-2 through FDDA-4.
Availability of Technology
Not applicable since no remedial technologies will be
used.
Qualified engineers and contractors arc available to
design and implement this alternative.
Same as FDDA-2, FDDA-4 and FDDA-5.
Same as FDDA-2, FDDA-3 and FDDA-5.
Same as FDDA-2 through FDDA-4.
. vj*.
Capita] Costs
$0
$3,100,000
$3,400,000
$1,000,000
$4,500,000
Annual Operation, Maintenance
and Monitoring
$41,000
$4,300,000
to
$5,100,000
$4,100,000
to
$5,700,000
$1,700,000
$5,300,000
to
$7,700,000
Periodic Costs
143,000
$130,000
$120,000
$110,000
$130,000
TOTAL
$84,000
$7,530,000
to
$8,330,000
$7,620,000
to
$9,220,000
$2,810,000
$9,930,000
to
$12,330,000
K-2
-------
TABLE K-3
COMPARATIVE ANALYSIS FOR DOWNGRADIENT GROUNDWATER REMEDIAL ALTERNATIVES
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
EVALUATION CRITERIA
i GSA-1
GSA-2
OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT
Human Health Protection
The potential future risks will remain and RAOs will not be
achieved.
The potential future risks will be eliminated and RAOs will
be achieved.
Ecological Protection
The current and potential future risks will remain and
RAOs will not be achieved.
The current and potential future risks will be eliminated and
RAOs will be achieved.
COMPLIANCE WITH ARARs
Chemical Specific
Chemical specific ARARs will not be met for this
alternative.
This alternative will be designed and implemented to
comply with the chemical specific ARARs.
Location Specific
Location specific ARARs do not apply for this alternative.
This alternative will be designed and implemented to
eomplv with applicable location-specific ARARs.
Action Specific
Action specific ARARs do not apply for this alternative.
This alternative will be designed and implemented to
comply with applicable action-specific ARARs.
LONG-TERM EFFECTIVENESS AND PERMANENCE
Magnitude of Residual Risk
Current and potential future exposure to contaminants in
soil will continue to pose a potential residual risk.
Residual risks will be significantly reduced.
Adequacy and Reliability of
Controls
No controls are proposed for this alternative.
Alternative will provide long-term effectiveness and
permanence.
R
EDUCTION OF TOXICITY, MOBILITY AND VOLUME THROUGH TREATMENT
Treatment Process Used and
Materials Treated
No active treatment is proposed for this alternative.
Treatment of impacted soil is not anticipated; however, if
required, ex-situ treatment of the material will be
implemented.
Amount Destroyed or Treated
None
No treatment is anticipated with this alternative; however, il
required, concentrations will be reduced to allow for reuse
and disposal on-site beneath the landfill final cover system.
Degree of Expected Reductions
in Toxicity, Mobility or Volume
through Treatment
No reduction in toxicity, mobility or volume through
treatment will be achieved with this alternative.
No active treatment of the excavated material is anticipated
for this alternative; however, through re-use/disposal of the
material beneath the landfill final cover system, the
toxicity, mobility and volume of impacted material in the
GSA is sianifieantlv reduced.
Degree to which Treatment is
Irreversible
No treatment is proposed.
No treatment is anticipated.
K-3
-------
TABLE K-3
COMPARATIVE ANALYSIS FOR DOWNGRADIENT GROUNDWATER REMEDIAL ALTERNATIVES
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
EVALUATION CRITERIA
GSA-1
GSA-2
Type and Quantity of Residuals
Remaining after Treatment
Existing conditions will remain since no treatment or
removal is proposed.
No active treatment of the excavated material is anticipated
for this alternative; however, through excavation of the
impacted material, no residuals presenting exposure risks
will remain.
Degree to Which Treatment
Reduces Principal Threats
No treatment is proposed.
No active treatment of the excavated material is anticipated
for this alternative; however, through excavation of the
impacted material, the principal threats wilt be eliminated.
SHORT-TERM EFFECTIVENESS
Protection of Community During
Remedial Action
Not applicable
This alternative will not have significant short-term effects
on the local community.
Protection of Workers During
Remedial Action
Not applicable
Use of appropriate engineering controls, PPE, and training
will be incorporated into the alternative design to protect
workers,
Environmental Impacts
Not applicable
Limited environmental impacts are anticipated.
Time Until Remedial Action
Objectives are Achieved
RAO's will not be achieved through this alternative.
1 to 2 years
IMPLEMENTABILITY '
Ability to Construct and Operate
the Technology
Not applicable
Common technique, straight forward to implement.
Reliability of the Technology
Not applicable
Reliable technology to quickly and effectively eliminate
exposure risks.
Ease of Undertaking Additional
Remedial Actions, if necessary
This alternative will not limit or interfere with the ability to
implement or perform future remedial actions.
This alternative will not limit or interfere with the ability to
implement or perform future remedial actions.
Ability to Monitor Effectiveness
of Remedy
Not applicable
Confirmatory soil sampling and analysis is easily
implementable to measure the effectiveness of the remedy.
Ability to Obtain Approvals and
Coordinate with Other Agencies
Not applicable
The remedial action will be designed and implemented
under coordination with appropriate Federal and State
agencies.
K-3
-------
TABLE K-3
COMPARATIVE ANALYSIS FOR DOWNGRADIENT GROUNDWATER REMEDIAL ALTERNATIVES
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
EVALUATION CRITERIA
GSA-1
GSA-2
Availability of off-site
Treatment, Storage and Disposal
Services and Capacity
Not applicable
Excavated soil can be reused/disposed of on-site at one of
the landfill lobes beneath the final cover system.
Availability of Necessary
Equipment and Specialists
No equipment or specialists required for this alternative.
Equipment, materials and services for this alternative are
readily available.
Availability of Technology
Not applicable
Qualified engineers and contractors are readily available to
design and implement this alternative.
COSTS - net present value (7%) - 30 years
Capital Costs
$0
$184,000
Annual Operation, Maintenance
and Monitoring
$40,000
$0
Periodic Costs
$10,000
$16,000
TOTAL
$5(1,(MMJ
$200,000
K-3
-------
TABLE K-4
COMPARATIVE ANALYSIS FOR DOWNGRADIENT GROUNDWATER REMEDIAL ALTERNATIVES
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
EVALUATION CRITERIA
DGGW-1
DGGW-2
DGGW-3
DGGW-4
OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT
Human Health Protection
The potential future risk of potable groundwater use
will remain and RAOs will not be achieved.
Until the RAOs are achieved, institutional controls will
be in place to prevent groundwater use/exposure,
controlling human risks.
Until the RAOs are achieved, institutional controls will
be in place to prevent groundwater use/exposure,
controlling human risks.
Until the RAOs are achieved, institutional controls will
be in place to prevent groundwater use/exposure,
controlline human risks.
Ecological Protection
Not applicable
Not applicable
Not applicable
Not applicable
^ COMPLIANT WITH ARARs
Chemical Specific
Chemical specific ARARs will not be met.
This alternative will meet the RAOs apd therefore
comply with the chemical specific ARARs.
This alternative will meet the RAOs and therefore
comply with the chemical specific ARARs.
This alternative will meet the RAOs and therefore
comply with the chemical specific ARARs.
Location Specific
Location specific ARARs do not apply for this
alternative.
This alternative can be designed and implemented to
comply with applicable location specific ARARs; this
alternative requires the least amount of disruption to
the resource areas and ecological reeqnors during
implementation.
This alternative can be designed and implemented to
comply with applicable location specific ARARs; this
alternative requires a moderate to high level of
disruption to the resource areas and ecological
receptors during construction.
This alternative can be designed and implemented to
comply with applicable location specific ARARs; this
alternative requires the highest level of disruption to
the resource areas and ecological receptors during
construction.
Action Specific
Action specific ARARs do not apply for this
alternative.
This alternative can be implemented to comply with
applicable action-specific ARARs. :
This alternative can be implemented to comply with
applicable action-specific ARARs.
This alternative can be implemented to comply with
applicable action-specific ARARs.
LONG-TERM EFFECTIVENESS AND PERMANENCE
Magnitude of Residual Risk
Potential future exposure to contaminants in
groundwater will continue to pose a residual risk.
Until the achievement of site RAOs, implementation of
institutional controls will reduce potential use and
exposure to impacted groundwater; therefore residual
risk is low.
Comparable to DGGW-2 and DGGW-4.
Comparable to DGGW-2 and DGGW-3.
Adequacy and Reliability of
Controls
No controls are proposed.
Institutional controls should effectively limit human
exposure to impacted groundwater until RAOs are
achieved. Monitoring of groundwater will be required
to measure the reliability of the alternative.
Institutional controls should effectively limit human
exposure to impacted groundwater until RAOs are
achieved. Monitoring of the extraction system's
effectiveness will be required to measure the reliability
of the alternative. Extraction and treatment system
components will require maintenance, upkeep and
potentially replacement overtime to ensure reliability
over time.
Same as DGGW-3.
f©H0fcl ©RfTOXlCITY;- MOBIliffJ®,N D VOiaUMETHROUGHiFRBkTMENI^^Mipi^fy' .
JfSV: • - '
Treatment Process Used and
Materials Treated
No active treatment is proposed for this alternative.
Natural attenuation processes with or without
enhancements, including biodegradation. dispersion,
dilution, adsorption, volatilization andfor chemical and
biological stabilization or destruction of contaminants,
will address impacted groundwater.
A combination of ex-situ technologies such as air
stripping, advanced oxidation processes and/or metals
treatment, in addition to one or more pretreatment
steps will treat impacted groundwater (to be
determined during remedial design phase).
Same as DGGW-3.
Amount Destroyed or Treated
No active treatment is proposed for this alternative.
Natural attenuation processes are anticipated to reduce
contaminants over time.
An estimated 75 gpm of groundwater will be treated
through the treatment system.
Comparable to DGGW-3 (except at estimated 140
spin).
Degree of Expected Reductions
in Toxicity, Mobility or Volume
through Treatment
No reduction in toxicity, mobility or volume through
treatment will be achieved with this alternative.
The degree that this alternative will reduce the toxicity,
mobility, and volume of COCs through natural
attenuation is moderate compared to other alternatives.
Provides a high degree of reduction in toxicity and
mobility and moderate degree in volume reduction.
Provides a high level of reduction in toxicity, mobility
or volume through treatment.
Degree to which Treatment is
Irreversible
No active treatment is proposed.
Natural degradation processes with or without
enhancements will be permanent.
Ex-situ groundwater treatment will be permanent.
Ex-situ groundwater treatment will be permanent.
K-4
-------
TABLE K-4
COMPARATIVE ANALYSIS FOR DOWNGRADIENT GROUNDWATER REMEDIAL ALTERNATIVES
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
EVALUATION CRITERIA
DGGW-1
DGGW-2
DGGW-3
DGGW-4
Type and Quantity of Residuals
Remaining after Treatment
No active treatment is proposed.
No ex-situ residuals.
Low to moderate volume of treatment residuals (e.g.,
sludge from metals treatment) anticipated to be
generated, requiring off-site disposal.
Moderate to high volume of treatment residuals (e.g.,
sludge from metals treatment) anticipated to be
generated, requiring off-site disposal.
Degree to Which Treatment
Reduces Principal Threats
No active treatment is proposed.
Upon achieving RAOs, the potential human risks to
downgradient groundwater will be elyninaied.
.A
Upon treatment of contaminants in groundwater, the
potential human risks to downgradient groundwater
will be eliminated.
Upon treatment of contaminants in groundwater, the
potential human risks to downgradient groundwater
will be eliminated.
SHORT-TEBWFFEGTiVENESS
Protection of Community During
Remedial Action
Not applicable since no remedial actions are included
in this alternative.
No impacts to the community are anticipated for this
alternative. 1
No significant short-term impacts to the local
community are anticipated for this alternative;
however, there may be a slight increase in vehicular
traffic to the site during construction activities.
Similar to DGGW-3.
Protection of Workers During
Remedial Action
Not applicable.
Work will be performed in accordance with applicable
OSHA standards. Site-specific health and safety
plant s) will be developed to protect site workers.
Similar to DGGW-2 and DGGW-4
Similar to DGGW-2 and DGGW-3.
Environmental Impacts
Not applicable.
Impacts to the wetland resource areas are anticipated
to be limited during activities.
Impacts to the wetland resource areas are anticipated
to be moderate to high during construction activities
due to the location of the extraction wells within the
resource area.
Impacts to the wetland resource areas is anticipated to
be high during construction activities due to the
location of the extraction wells within the resource
area.
Time Until Remedial Action
Objectives are Achieved
Ability to Construct and Operate
the Technology
ilAOs will not be achieved through this alternative.
Not applicable.
With Source Control - 67 to 79 years
Without Source Control - 81 to 98 years
With Source Control - 57 to 68 years
Without Source Control - 70 to 86 years
•JTABIt
No construction activities are planned for this
alternative other than installation of additional
monitoring wells; monitoring activities are easily
implementable. If enhancements are deemed
necessary, they will also be moderately implementable.
Construction in wetland resource areas will have
moderate implementability.
With Source Control - 40 to 49 years
Without Source Control - 53 to 66 years
Extensive construction in wetland resource areas may
be difficult to implement.
Reliability of the Technology
Not applicable.
Site characterization data indicate thai natural
attenuation processes are effectively and reliably
degrading contaminants.
Groundwater extraction is a demonstrated and reliable
method for capturing and collecting impacted
groundwater. In addition, the ex-situ treatment
components are effective in treating groundwater to
the remedial goals
Similar to DGGW-3.
Ease of Undertaking Additional
Remedial Actions, if necessary
This alternative will not limit or interfere with the
ability to implement or perform future remedial
actions.
Similar to other DGGW alternatives evaluated.
Similar to other DGGW alternatives evaluated.
Similar to other DGGW alternatives evaluated.
Ability to Monitor Effectiveness
of Remedy
Not applicable.
Groundwater sampling and analysis to evaluate
contaminant levels is easily implementable.
Groundwater monitoring to demonstrate hydraulic
containment and to determine contaminant levels is
easily implementable. Treatment system effluent will
be monitored on a routine basis to evaluate the
effectiveness of the treatment system and document
that discharge requirements are being met.
Same as DGGW-3.
K-4
-------
TABLE K-4
COMPARATIVE ANALYSIS FOR DOWNGRADIENT GROUNDWATER REMEDIAL ALTERNATIVES
Remedial Investigation and Feasibility Study
Sutton Brook Disposal Area Superfund Site - Tewksbury, MA
EVALUATION CRITERIA
DGGW-1
DGGW-2
DGGW-3
DGGW-4
Ability to Obtain Approvals and
Coordinate with Other Agencies
Not applicable since no remedial actions are included
in this alternative; therefore, no approvals or
coordination required.
The remedial action will be designed and implemented
under coordination with appropriate Federal and State
aeencies.
Similar to DGGW-2 and DGGW-4.
Similar to DGGW-2 and DGGW-3.
Availability of off-site
Treatment, Stowage and Disposal
Services and Capacity
Not applicable.
Not applicable.
Discharge of the treated groundwater will be to surface
water or the local POTW.
Discharge of the treated groundwater will be to surface
water or the local POTW.
Availability of Necessary
Eauicment and Specialists
No equipment or specialists required for this
alternative.
Equipment, materials and services for this alternative
are readily available.
Similar to DGGW-2 and DGGW-4.
Similar to DGGW-2 and DGGW-3.
Availability of Technology
Not applicable since no remedial technologies will be
used.
Qualified engineers and contractors are available to
design and implement this alternative.
Similar to DGGW-2 and DGGW-4.
Similar to DGGW-2 and DGGW-3.
lii\ V ¦ /:V, -r-
r • COSTS - net pre$W%vaiue (7%) - 30 yearn
Capital Costs
$0
$230,000
$2,900,000
$4,500,000
Annual Operation, Maintenance
and Monitoring
$41,000
$1,400,000
$6,800,000
to
$9,800,000
$6,500,000
to
$12,200,000
Periodic Costs
$43,000
$120,000
$130,000
$130,000
TOTAL
$84,000
$1,750,000
$9,830,000
to
$12,830,000
$11,130,000
to
$16,830,000
DGGW-3 and DGGW-4 O&M cost range incorporates: 30 years of system operation with 30 years of groundwater monitoring - tow; discharge to surface water, high: discharge to
K-4
-------
Table L-1: Groundwater Cleanup Levels - Residential Scenario
Carcinogenic Chemical or
Concern
Cancer Classification
CJeanup Level
£ug/L)
Basis
RME Risk
1.1,2-Triehloreethar*
c
5
MCL
3E-05
1,2-Dichloraetfiane
E2
5
MCL
4E-QS
1,2'Df chiorepm p a na
N/A
5
MCL
6E-96
t,4-D»chtorfbenEer«>
N/A
75
MCL
5E-Q5
1.4-Dioxane
52
4
risk
1E-Q6
AcrytonfWfl
B1
0.05
risk
1E-06
Benzene
A
5
MCL
2E-0S
Carton Tetrachloride
B2
S
MCL
3E-Q5
ChlorofQim
32
SO
MCL
6E-Q4
Melhyiene chtonOfl
32
5
MCL
1E-06
T etrBcNoroethen#
S1
5
MCL
7E-05
TnchJoroethene
N/A
5
MCL
4E-05
Vinyl Ch^ndf
A
2
MCL
6E-05
alpha-BHC
82
0008
rt$k
IE-06
ArodCir-1254
B2
0.5
MCL
3E-06
bistl-EthyihejtytJphthalate
52
8
MCL
3E-06
N-Nitfosodi-rvbutyiamine
52
0003
risk
1E-06
N -N itra sopyrro 11 d ine
B2
0,03
n»k
IE-06
o-Toluidine
N/A
0.2
risk
8E-G7
Arsenic
A
10
MCL
2E-Q4
Nor?-Carcinogenic Chemical
of Concern
Target Endpolnt
Cleanup Level
(ug/L)
Basis
RME Hazard Quotient
1,1,1-TricNoi'oelhane'
Liver
200
MCL
8E-C2
1,?-Dichiofo«thane
CNS
360
HQ
ie+w
1,1-DichlDroethene T
Liver
7
MCL
5E-02
1,2-DichloroethervB (total)
Liver
100
MCL
3E+00
1,4-Dioxane
Liver
4
risk
3E-Q3
2-Buienone
Developmental
4000
Health Advisory
7E-01
4-M ethyl- 2 -pentanone
Liver, Kidney
800
HQ
1E+00
Acetone
Kidney
5600
HQ
1E+00
Aerytonitrtle
Reproductive
0.05
risk
1E»02
Benzene
Immune System
5
MCL
3E-01
Carbon lelracWond®
Liver
s
MCL
3E+00
cis-l,2'0:chloroaihone
Blood
70
MCL
2E+00
Eihyf methacryfste
Kidney
260
HQ
1E*00
Elhylbertzene
Liver: Kidney
700
MCL
2E+00
MsJhyiana chloride
Liver
5
MCL
9E-03
n-Propylber*ens
N/A
52
HQ
1E+00
Sfyrene 1
Blood; Liver
100
MCL
2E-01*
Tetrahydrofuran
N/A
227
HQ
1E+00
Toluene
Kidney
1000
MCL
2E+00
Vinryl chteHKfs
Liver
2
MCL
9E-02
Xylenes (total)
General Toxicity
fOOOO
MCL
1E+02
2-Methylpi-wcJ
Genera! Toxtcrty; CNS
540
HQ
1E-»00
3-/4-Methyf£hertOi
Gerterai Toxicity: CNS
470
NQ
1E+00
DtsfZ-Ethythexyiiprnhfliate
Liver
B
MCL
5E-D2
Naphthalene
General Toxicity
1D0
Health Advisory
36+01
phenol
Developmental
2000
Health Advisory
6E-01
Pyridine
Liver
9
HQ
1E+00
Aroc)Qf-l2S4
Immune ayttem
0,5
MCL
2E+00
Antimony
General Toxicity
a
MCL
1E+00
Arsenic
Skin
10
MCL
3E*GQ
Beryllium
Gastrointestinal System
4
MCL
3E-Q1
Cadmium
Kidney
5
MCL
9E-01
Chromium
Gastrointestinal System
109
MCL
2E+01
Lead'
CNS
15
MCL
NA
Manganese
CNS
m
Health Advisory
6E-01
Saiemum'
Uver
50
MCL
7E-01
Silver
Skin
100
Health Advisory
2E+00
Thallium
Blood
2
MCL
2E+00
Zinc
Blood
2990
Health Advisory
5E-01
Key
Health Advisory - Lifetime Health Advisory presented tn EPA-022-R-O4-QQS: Winter 2004
MCL - Maximum Contaminant Level
HQ - Hazard Quotient
NA • Nat applicable
(1) This contaminant did not exceed a hazard quotient of 1 during calculations. However, the maximum detected concentration exceeded MCLs, Therefore, the cleanup level has been
astaiaiiahed as lie MCL
Page 1 of 1
Section I TabtM-HH-081607.xls
-------
Table L-2: Soil Cleanup Levels for the Protection of Residential Direct Contact Exposures
Group 4, Upland Soil
Carcinogenic Chemical of
Concern
Cancer Classification
Cleanup Level
img?kg)
Basts
RME Risk
B©nzo(a)antfira oene
N/A
44
risk
1E-Q5
Benzo(a)pyrene
B2
0,44
risk
1E-05
Bei20(b)fluoranlflene
82
4.4
risk
1E-05
BenzcKkjfluorantfiene
82
44
risk
1E-Q5
Dibe nzf a, h ) anthracene
B2
0.44
nsk
1E-05
Ir*ten0(1 2,3-cdJpyrene
82
44
risk
1E-05
Sum of Carcinogenic Risk:
6E-05
Key
Page 1 of 1
Section LTables-HH-081B07.xls
-------
Table L-3: Soil Cleanup Levels for the Protection of Ecological Receptors
Habitat
Type/Name
Exposure
Medium
COC
Protective
Level
Units
Basis
Assessment
Endpoint
Former Drum Disposal
Area
Soil
1,2.4-Trimethylbenzene
u
mg/kg
Site-Specific NOAEL
- Sustainability (survival, growth,
reproduction) of local populations of
carnivorous wildlife (robin)
- survival and growth of invertebrtates
- abundance and diversity of plants
1,3,5-TrimethyIbenzene
1.1
mg/kg
Site-Specific NOAEL
bis{2-Ethylhexyl)phthalate
2.3
mg/kg
HQ = 0.1
Di-n-octylphthalate
0,1
mg/kg
HQ = 0.1
Ethylbenzene
1.1
mg/kg
Site-Specific NOAEL
Naphthalene
1
mg/kg
Site-Specific NOAEL
Toluene
1.1
mg/kg
Site-Specific NOAEL
Xylenes (total)
1.1
mg/kg
Site-Specific NOAEL
Garage and Storage Area
Soil
Di-n-octylphthalate
0.4
mg/kg
HQ = 0.1
- Sustainability (survival, growth,
reproduction) of local populations of
carnivorous wildlife (robin)
- survival and growth of invertebrtates
Lead
65
mg/kg
HQ = 0.1
Zinc
190
mg/kg
Site-Specific LOAEL
Notes:
HQ - Hazard Quotient
NOAEL - No Observable Adverse Effect Level
COC - Chemical of Concern
LOAEL - Lowest Observable Adverse Effect Level
Page 1 of 1
Section L Tables-Eco-081607.xls [L-5]
-------
Table L-4: Surface Water Cleanup Levels for the Protection of Ecological Receptors
Habitat
Type/Name
Exposure
Medium
COC
Protective
Level
Units
Basis
Assessment
Endpomt
Upper Sutton Brook - Site
Channel
Surface Water
4,4-DDT
0.001
ug/L
NRWQC
- Survival and growth of potential fish
and invertebrate communities
Ethylbenzene
7.3
ug/L
Site-Specific NOAEL
Toluene
9.8
ug/L
Site-Specific NOAEL
Xylenes (total)
13
ug/L
Site-Specific NOAEL
Notes:
NOAEL - No Observable Adverse Effect Level
COC - Chemical of Concern
NRWQC - National Recommended Water Quality Criterion
Page 1 of 1
Section L Tables-Eco-Q816Q7.xls [L-4]
-------
Table L-5: Sediment Cleanup Levels for the Protection of Ecological Receptors
Habitat
Type/Name
Exposure
Medium
COC
Protective
Level
Units
Basis
Assessment
Endpoint
Upper Sutton Brook - Site
Channel
Sediment
1,2,4-Trimethylbenzene
1.3
rng/kg
Site-Specific NOAEL
- Survival and growth of local
populations of benthic invertebrates
1,3,5-Trimethyl benzene
1.2
mg/kg
Site-Specific NOAEL
2-Methylphenol
0.1
mg/kg
Site-Specific NOAEL
3-/4-Methylphenol
0.6
mg/kg
Site-Specific NOAEL
4-Methyl-2-pentanone
0.04
mg/kg
Site-Specific NOAEL
Acetone
0.07
mg/kg
Site-Specific NOAEL
Carbon Disulfide
0.001
mg/kg
Site-Specific NOAEL
Chloroettiane
0.03
mg/kg
Site-Specific NOAEL
Ethyl benzene
0.09
mg/kg
Site-Specific NOAEL
Toluene
0.06
mg/kg
Site-Specific NOAEL
Xylenes (total)
0.13
mg/kg
Site-Specific NOAEL
Notes:
NOAEL. - No Observable Adverse Effect Level
COC - Chemical of Concern
Page 1 of 1
Section L Tables-Eco-081607.xls [L-3]
-------
TABLE M-1
ALTERNATIVE LF-2b
CHEMICAL SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
S ¦ -i f
Federal Regulatory Requirements
Federal Safe Drinking Water Act
(SDWA) Maximum Contaminant Levels
(MCLs) (40 CFR Part 141)
Relevant and appropriate
MCLs are enforceable standards that regulate Hie
concentration of specific organic and inorganic contaminants
that have been determined to adversely affect human health
in public drinking water supplies. MCLs are relevant and
appropriate for the groundwater at the Site because the
aquifer is a potential source of drinking water.
MCLs were used in determining groundwater preliminary
remediation goals (PRGs) for site contaminants where such
contaminant levels have been established. Under the LF-2b
component of the selected remedy, the groundwater approach
(MNA for the northern lobe; and partial containment with a
vertical barrier and groundwater extraction and treatment for
the southern lobe) will over time prevent groundwater
exceeding MCLs from migrating beyond the point of
compliance (edge of the waste management area).
EPA Risk Reference Doses {RfDs)
To be considered
RfDs are dose levels developed by EPA for use in estimating
the non-carcinogenic risk resulting from exposure to toxic
substances.
RfDs were used to assess health risks due to exposure to non
carcinogenic chemicals in groundwater, and to develop of
acceptable groundwater PRG concentrations. Under the LF-
2b component of the selected remedy, the groundwater
approach {MNA for the northern lobe; and partial containment
with a vertical barrier and groundwater extraction and
treatment for the southern lobe) will over time prevent
groundwater exceeding PRGs from migrating beyond the
point of compliance (edge of the waste management area).
Groundwater
EPA Human Health Assessment Cancer
Slope Factors (CSFs)
To be considered
CSFs are developed by EPA for health effects assessments
or evaluation by the Human Health Assessment Group.
These values present the most up-to-date cancer risk potency
information and are used to compute the individual
incremental cancer risk resulting from exposure to
carcinogens.
CSFs were used to compute the individual cancer risk
resulting from exposure to contaminants and in the
development of acceptable groundwater PRG concentrations.
Under the LF-2b component of the selected remedy, the
groundwater approach (MNA for the northern lobe; and partial
containment with a vertical barrier and groundwater extraction
and treatment for the southern lobe) will over time prevent
groundwater exceeding PRGs from migrating beyond the
point of compliance (edge of the waste management area).
Guidelines for Carcinogen Risk
Assessment (EPA/630/P-03/001F,
March 2005)
To be considered
Guidance values were used to evaluate the potential
carcinogenic hazard caused by exposure to contaminants.
Cancer risks identified will be addressed by the LF-2b
component of the selected remedy.
Supplemental Guidance for Assessing
Susceptibility from Early-Life Exposure
to Carcinogens (EPA/630/R-03AX33F,
March 2005)
To be considered
Guidance values were used to evaluate the potential
carcinogenic hazard to children caused by exposure to
contaminants.
Child cancer risks identified will be addressed by the LF-2b
component of the selected remedy.
EPA Office of Water, Drinking Water
Health Advisories EPA 822-R-Q8-013
To be considered
Health Advisories (HAs) are estimates of acceptable drinking
water levels for chemical substances based on health affects
information; an HA is not a legally enforceable Federal
standard, but serves as technical guidance to assist federal,
state and local officials. HAs were used if constituents did not
have promulgated MCLs.
HAs were used to develop acceptable groundwater PRG
concentrations. Under the LF-2b component of the selected
remedy, the groundwater approach (MNA for the northern
lobe; and partial containment with a vertical barrier and
groundwater extraction and treatment for the southern lobe)
will over time prevent groundwater exceeding PRGs from
migrating beyond the point of compliance (edge of the waste
management area).
Suiwn Brook Disposal Area SF Site
Tewksbunr, MassacfKisetts
Page 1 of 2
Record of Decision
September 2007
-------
TABLE M-1
ALTERNATIVE LF-2b
CHEMICAL SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
•*y~:'-'a^MsciUl
Groundwater
(Cont'd)
State Regulatory Requirements
Massachusetts Groundwater Quality
Standards (314 CMR 6,00)
Applicable
These standards consist of ground water classifications,
which designate and assign the uses for which the various
ground waters of the Commonwealth shall tie maintained and
protected; water quality criteria necessary to sustain the
designated uses; and regulations necessary to achieve the
designated uses or maintain the existing ground water quality.
The GWQSs set numeric limits for certain contaminants as
well as a pH range. They were used when they were more
stringent than Federal MCLs.
Groundwater beneath the Site is mapped in a potentially
productive aquifer with the potential for potable water use.
Under the LF-2b component of the selected remedy, the
groundwater approach (MNA for the northern lobe; and partial
containment with a vertical barrier and groundwater extraction
and treatment for the southern lobe) will over time prevent
groundwater exceeding PRGs from migrating beyond the
point of compliance (edge of the waste management area).
Massachusetts Drinking Water
Standards (310 CMR 22.00}
Relevant and appropriate
These standards establish Massachusetts MCLs for organic
and inorganic contaminants that have been determined to
adversely affect human health in public drinking water
systems. The aquifer on-site is not a public water system, but
these requirements ane R&A because the aquifer has the
potential to be used as a source of drinking water. These
requirements were used when they were more stringent than
Federal MCLs.
Under the LF-2b component of the selected remedy, the
groundwater approach (MNA for the northern lobe; and partial
containment with a vertical barrier and groundwater extraction
and treatment for the southern lobe) will over time prevent
groundwater exceeding PRGs from migrating beyond the
point of compliance (edge of the waste management area).
Massachusetts DEP Office of Research
and Standards Guidelines (ORSGs)
To be considered
The Massachusets DEP Office of Research and Standards
issues guidance for chemicals other than those with
Massachusetts MCLs in drinking water. ORSGs are
concentration of chemicals in drinking water, at or below
which, adverse health effects are unlikely to occur after
chronic (lifetime) exposure. These guidance values were
used when constituents did not have promulgated MCLs.
Under the LF-2b component of the selected remedy, the
groundwater approach (MNA for the northern lobe; and partial
containment with a vertical barrier and groundwater extraction
and treatment for the southern lobe) will over time prevent
groundwater exceeding PRGs from migrating beyond the
point of compliance (edge of the waste management area).
Sutton Brook Disposal Area SF Siie
Tewksbury, Massachusetts
Page 2 of 2
Record of Decision
September 200?
-------
TABLE M-2
ALTERNATIVE LF-2b
ACTION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
. x«f>*edhi8(iiR*
->SMub|
Federal Regulatory Requirements
RCRA Subtitle G - Hazardous Waste
identification and Listing Regulations (40 CFR
Parts 260-262 and 40 CFR 264.13)
Applicable
Massachusetts has been delegated the authority to administer
these RCRA standards through its state hazardous waste
management regulations. These provisions have been adopted by
tha State. These regulations include rules to identify hazardous
waste and a requirement to obtain a detailed chemical and
physical analysis of a representative sample of any hazardous
wastes prior to treatment, storage, or disposal.
Because RCRA-type (listed or characteristic) hazardous
wastes were disposed of at the Site during the operation of the
landfill, this requirement was determined to be applicable. Any
media generated as part of monitoring activities and
groundwater extraction and treatment will be tested for
hazardous waste characteristics. If determined to be
hazardous waste, then they will be stored, transported, or
disposed of in accordance with 40 CFR Part 264.
RCRA Subtitle C - Closure and Post-Closure
(40 CFR Subpart G, 264,111 and 264.117)
Appl (cable
Massachusetts has been delegated the authority to administer
these RCRA standards through its state hazardous waste
management regulations. These provisions have been adopted by
the State. 40 CFR 264.111 identifies standards for closures of
hazardous wastes facilities; 40 CFR 11? identifies post-closure
standards for maintenance of facilities.
Because RCRA-type (listed or characteristic) hazardous
wastes were disposed of at the Site during the operation of the
landfill, this requirement was determined to be applicable. The
LF-2b component of the selected remedy will be designed and
implemented to comply with this ARAR,
RC RA Subtitle C - Landfills (40 CFR Subpart
N, 264.310)
Applicable
Massachusetts has been delegated the authority to administer
these RCRA standards through its state hazardous waste
management regulations. These provisions have been adopted by
the State. These regulations establish the minimum requirements
for final covers of hazardous waste landfills.
Because RCRA-type (listed or characteristic) hazardous
wasles were disposed of at the Site during the operation of the
landfill, this requirement was determined to be applicable. The
LF-2b component of the selected remedy will be designed and
implemented to comply with this ARAR.
Waste
RCRA 40 CFR 264 Subpart I, Use and
Management of Containers
Applicable if a container is
used in the remedial
action
Massachusetts has been delegated the authority to administer
these RCRA standards through its state hazardous waste
management regulations. These provisions have been adopted by
the State. This regulation establishes requirements for the storage
of containers of hazardous waste.
For the groundwater portion of the LF-2b component of the
selected remedy, because RCRA-type (listed or characteristic)
hazardous wastes were disposed of at the Site during the
operation of the landfill, which included disposal after 1980, if
a container is used to store hazardous waste, then LF-2b will
be implemented to comply with this ARAR.
RCRA 40 CFR 264 Subpart J, Tank Systems
Applicable if a tank system
is used in the remedial
action
Massachusetts has been delegated the authority to administer
these RCRA standards through Its state hazardous waste
management regulations. These provisions have been adopted by
the State. This regulation establishes requirements for the use of
tank systems for storing or treating hazardous waste.
For the groundwater portion of the LF-2b component of the
selected remedy, because RCRA-type (listed or characteristic)
hazardous wastes were disposed of at the Site during the
operation of the landfill, which included disposal after 1980, if
a tank system is used to store hazardous waste, then LF-2b
will be implemented to comply with this ARAR.
RCRA 40 CFR 264 Subpart L, Waste Piles
Applicable if a waste pile
Is used in the remedial
action
Massachusetts has been delegated the authority to administer
these RCRA standards through its state hazardous waste
management regulations. These provisions have been adopted by
the State. This regulation establishes requirements for the use of
piles for storing or treating hazardous waste.
Because RCRA-type (listed or characteristic) hazardous
wastes were disposed of at the Site during the operation of the
landfill, which included disposal after 1980, if a pile is used to
store hazardous waste (potentially such as the excavated
sediments prior to consolidation into the landfill lobes), then
the LF-2b component of the selected remedy will be
implemented to comply with this ARAR.
RCRA 40 CFR 264 Subpart X, Miscellaneous
Units
Applicable if a
miscellaneous unit is used
in the remedial action
Massachusetts has been delegated the authority to administer
these RCRA standards through its state hazardous waste
management regulations. These provisions have been adopted by
the State. This regulation establishes requirements for the use of
miscellaneous units for treating, storing, or disposing of hazardous
waste.
Because RCRA-type (listed or characteristic) hazardous
wastes were disposed of at the Site during the operation of the
landfill, which included disposal after 1980, if a miscellaneous
unit is used to store hazardous waste, then the LF-2b
component of the selected remedy wilt be implemented to
comply with this ARAR.
Sutton Brook Disposal Area SF Site
Tewksbury, Massachusetts
Page 1 of 5
Fteeord of Decision
September 2007
-------
TABLE R/i*2'
ALTERNATIVE LF-2b
ACTION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
RCRA 40 CFR 264 Subpart AA, Air Emission
Standards for Process Vents
Applicable if a process
vent is used and if
thresholds are met
This regulation establishes air emission standards for process
vents, closed-vent systems, and control devices at hazardous
waste facilities.
For the groundwater portion of the LF-2b component of the
selected remedy, if a process vent is used in the remedial
action and if applicable thresholds are met. then air emission
controls will be implemented during groundwater treatment to
comply with this regulation.
RCRA 40 CFR 284 Subpart BB, Air Emission
Standards for Equipment Leaks
Applicable if equipment
covered by this standard
is used and if thresholds
are met
This regulation contains air pollutant emission standards for
equipment leaks at hazardous waste TSD facilities. This subpart
applies to equipment that contains or contacts hazardous wastes
with organic concentrations of at least 10 percent by weight.
For the groundwater portion of the LF-2tj component of the
selected remedy, if equipment covered by this standard is
used in the remedial action and handles hazardous wastes at
concentrations that meet this rule's threshold, then a leak
detection and repair program will be Implemented during
groundwater treatment to compty with this regulation.
RCRA 40 CFR 264 Subpart CC, Air Emission
Standards for Tanks, Surface Impoundments
arid Containers
Applicable if a tank or
container is used and if
thresholds are met
This regulation establishes air emission standards for facilities that
treat store, or dispose hazardous wastes in tanks, surface
impoundments, or containers.
Any media generated as part of monitoring activities and
groundwater treatment will be tested for hazardous waste
characteristics. If determined to be hazardous waste, then
they will be stored, transported, or disposed of in accordance
with 40 CFR Part 264. If a tank or container is used in the
remedial action and if applicable thresholds are met, then air
emission controls will be implemented during groundwater
treatment to oompiy with this requlation.
Waste (cont'd)
RCRA 40 CFR 264 Subpart DD, Containment
Buildings
Applicable if a building is
used to house treatment
equipment
This regulation contains design, operating, closure and post-
closure standards and requirements for the storage and treatment
of hazardous waste in containment buildings.
For the groundwater portion of the LF-2b component of the
selected remedy, if a building is used to house treatment
equipment, then the design, operation, closure, and post-
closure of the treatment building for LF-2b will comply with this
regulation.
Technical Memorandum RE: Revised
Alternative Cap Design Guidance Proposed for
Unlined, Hazardous Waste Landfills in EPA
Region 1 (February 5,2001),
To be considered
This memo presents an alternative cover design for hazardous
waste landfills capped under CERCLA within Region 1.
This TBC will be considered in the design of the final cover for
the landfill lobes in meeting the RCRA Subtitle C hazardous
waste landfill final cover requirements.
Presumptive Remedy for CERCLA Municipal
Landfill Sites (OSWER Directive No, 9355.0-
49F)
To be considered
This guidance outlines a streamlined approach to the scoping
(planning) stages of the RI/FS in the process of closing municipal
landfills under CERCLA, with containment as the presumptive
remedy. This directive also provides guidance regarding the
appropriate level of detail appropriate for risk assessment of
source areas and characterization of hot spots.
This guidance was followed in the development of the RI/FS,
and the LF-2b component of the selected remedy will be
designed and implemented to comply with this requirement.
State Regulatory Requirements
Massachusetts Hazardous Waste
Management Standards (310 CMR 30.500)
Applicable
These rules are used to identify, manage, and dispose of
hazardous waste. Closure and post-closure standards are spelled
out.
The LF-2b component of the selected remedy will meet all
closure/post-closure standards. Any media generated as part
of monitoring activities and groundwater remedial action will
be tested for hazardous waste characteristics. If determined
to be hazardous waste, then they will be stored, transported,
or disposed of in accordance with these rules.
Sutton Bitxik Disposal Area SF Site
Tewksbury, Massachusetts
Page 2 of 5
Record of Decision
September 200?
-------
TABLE M-2
ALTERNATIVE LF-2b
ACTION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbuiy, Massachusetts
I
|
>S
3
|
il
Waste (cont'd)
Massachusetts Technical Standards for
Hazardous Waste Facilities (310 CMR 30,600,
310 CMR 30,633, 310 CMR 30,640, 310 CMR
30.560, 310 CMR 30.680, 310 CMR 30.690)
Applicable
These rules set standards for the design, performance, operation,
maintenance, and monitoring of hazardous waste facilities. For
hazardous waste landfills, these rules establishes performance
standards for iow permeability covers, post-closure care, and
groundwater monitoring. These rules also prescribe requirements
for trie use of containers and tanks to treat or store hazardous
waste.
The final landfill cover, post-closure care, and groundwater
monitoring can be designed and implemented to comply with
this ARAR. For the groundwater portion of the LF-2b
component of the selected remedy, if containers or tank
systems are used to store or treat hazardous waste, then IF-
2b will be implemented to comply with this ARAR. Also, if piles
are used to store hazardous waste (potentially such as the
excavated sediments prior to consolidation into one of the
landfill lobes), then LF-2b will be implemented to comply with
this ARAR.
MassDEP Landfill Technical Guidance,
revised, May 1997
To be considered
This technical guidance outlines trie closure process and design
requirements for unlined landfills in Massachusetts.
This guidance was used in the remedial alternative evaluation
and will be used during the landfill closure process.
Federal Regulatory Requirements
Clean Water Act Section 402 National
Pollutant Discharge Elimination System
(NPDES) (40 CFR Part 122-125 and 131)
Applicable
This act and regulations establish discharge limitations, monitoring
requirements, and best management practices. Point-source
discharges of effluent to surface water must comply with NPDES
requirements (e.g., federal and state ambient water quality criteria
(AWQC)).
On-site discharges to surface waters, including Sutton Brook
and adjacent wetlands, shall meet these substantive discharge
standards. These discharge limitations shall also be used to
develop monitoring standards for surface waters.
Clean Water Act (CWA) Ambient Water Quality
Criteria (AWQC) (33 USC 1251 etseq.) (40
CFR 122.44)
Relevant and appropriate
Federal AWQC are recommended (non-enforceable) criteria
published by EPA and provided to the States. AWQC are listed for
protection of ecological and human health for approximately 160
contaminants. AWQC are used in establishing State water quality
standards.
If treated groundwater is discharged to surface water, it will be
treated as needed to comply with State water quality
standards based on AWQC. Surface water monitoring will be
performed. These standards will be used to help assess the
effectiveness of the groundwater treatment.
Clean Water Act (CWA) Pretreatment
Regulations for Discharges to a POTW (40
CFR Part 403
Applicable if treated
groundwater is discharged
to the POTW
These regulations prohibit the introduction of pollutants into a
publidy owned treatment works (POTW) and has pretreatment
requirements for sources to a POTW
If treated groundwater is discharged to the local POTW, it will
be treated as need to comply with these pretreatment
requirements.
State Regulatory Requirements
Surface Water
Mass. Clean Waters Act - MassDEP Surface
Water Discharge Permit Program (314 CMR
3.00; MGL c. 21 Sections 26-53)
Applicable
This act and program establish the requirements intended to
maintain the quality of surface waters by controlling the direct
discharge of pollutants to surface waters. Direct discharge of
wastewater to surface waters must meet effluent discharge limits
established by this program.
Any on-site discharges to surface waters, including Sutton
Brook and adjacent wetlands, shall meet these substantive
discharge standards. These discharge limitations shall also
be used to develop monitoring standards for surface waters.
Massachusetts Surface Water Quality
Standards (314 CMR 4.00)
Applicable
The Massachusetts Surface Water Quality Standards designate
the most sensitive uses for which the various waters of the
Commonwealth shall be enhanced, maintained and protected;
which prescribe the minimum water quality criteria required to
sustain the designated uses; and which contain regulations
necessary to achieve the designated uses and maintain existing
water quality including, where appropriate, the prohibition of
discharges. These regulations limit or prohibit discharges of
pollutants to surface waters to ensure that the surface water quality
standards of the receiving waters are protected and maintained or
attained.
Any on-site discharges to surface waters, including Sutton
Brook and adjacent wetlands, shall meet these substantive
discharge standards. These discharge limitations shall also
be used to develop monitoring standards tor surface waters.
Sutton Brack Disposal Area SP Site
Tewksbury, Massachusetts
Page 3 of 5
Record of Decision
September 2007
-------
TABLE M-2
ALTERNATIVE LF-2b
ACTION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
SSSSiSftStali»s*;sssfe:iS
«Kf?f»diitiiiiiaaaaiiiii#ai-< ¦r-.•
MassDEP Surface Water Discharge Permit
Program (314 CMR 3.0Q)
Applicable
These regulations are intended to protect surface water bodies in
the Commonwealth by regulating the discharge into them. Direct
discharges of wastewater to surface waters must meet effluent
discharge limits established by this program.
Any on-site discharges to surface waters, including Sutton
Brook and adjacent wetlands, shall meet these substantive
discharge standards. These discharge limitations shall also
be used to develop monitoring standards for surface waters.
Surface Water
(Cont'd)
Massachusetts Pretreatment Standards for
Discharges to Wastewater Treatment Works
(314 CMR 12.00)
Applicable
These regulations prohibit the introduction of pollutants into a
publicly owned treatment works (POTW) and has pretreatment
requiremenis tor sources to a POTW
If treated groundwater is discharged to the local POTW, it will
be treated as need to comply with these pretreatment
requirements.
MassDEP Stormwater Management Policy
To be considered
The goal of the policy is to improve water quality arid address
water quantity problems within Massachusetts through the
implementation of performance standards for stormwater
management.
The LF-2b component of the selected remedy will be designed
and implemented to comply with this requirement.
Federal Regulatory Requirements
RCRA Subtitle C - Releases from Solid Waste
Management Units (40 CFR Subpart F,
264,95 and 264.96(a) and (c))
Applicable
These regulations identify specific monitoring requirements
applicable to hazardous waste facilities, including specifying the
point of compliance at which the groundwater protection standards
apply and at which monitoring must be conducted, as welt as
specifying the compliance period during which the groundwater
protection standard applies.
The LF-2b component of the selected remedy will be
implemented to comply with these requirements. EPA has
determined that the point of compliance at which the
groundwater protection standards apply Is the edge of the
waste management unit (the landfill lobes).
Underground injection (40 CFR Part 144)
Relevant and appropriate
These regulations provide regulatory compliance standards for
treatment facilities that inject wastes underground. The use at
wells to dispose of hazardous waste is prohibited.
If the performance of the LF-2b component of the selected
remedy utilizes underground injection for the treated
groundwater or uses an infiltration gallery or any other system
that disposes of treatment water or waste into groundwater as
the remediation technology, groundwater will be treated to be
non-hazardous prior to subsurface discharge.
Groundwater
Final OSWER Directive "Use of Monitored
Natural Attenuation at Superfund, RCRA
Corrective Action, and Underground Storage
Tank Sites (OSWER Dir. 9200.4-17P, 4/12/99)
To be considered
This guidance sets criteria for evaluating monitored natural
attenuation as a remedy at, among others, Superfund sites.
For Northern Lobe portion of the LF-2b component of the
selected remedy, monitored natural attenuation was
determined to be appropriate in accordance with this TBC.
Under LB-2b, for the Northern Plume groundwater,
contaminant levels at the point of compliance (at the edge of
the waste management unit) will be monitored consistent with
this guidance.
State Regulatory Requirements
MassDEP Underground injection Control
Regulations (310 CMR 27.00)
Applicable
These regulations are intended to protect underground sources of
drinking water by regulating the underground injection of
hazardous wastes, fluids used for extraction of minerals, oil, and
energy, and any other fluids having potential to contaminate
groundwater.
If the performance of the LF-2b component ot the selected
remedy utilizes underground injection for the treated
groundwater or uses an infiltration gallery or any other system
that disposes of treatment water or waste into groundwater as
the remediation technology, groundwater will be treated to be
non-hazardous prior to subsurface discharge.
MassDEP Groundwater Discharge Permit
Program {314 CMR 5.00)
Applicable
These regulations are intended to protect groundwater quality by
controlling the discharge of pollutants to the ground waters of the
Commonwealth to assure that these waters are protected for their
highest potential use. These regulations set effluent limits for the
discharge of pollutants to groundwater.
If the performance of the LF-2b component of the selected
remedy utilizes underground injection, infiltration gallery or any
other system that disposes of treatment water or waste into
groundwater as the remediation technology, groundwater will
be treated to meet the substantive requirements of these
regulations prior to subsurface discharge.
Massachusetts Well Decommissioning
Requirements (313 CMR 3.03)
Applicable
These regulations provide for certain notification requirements
upon well abandonment.
These regulations will be followed to the extent that the
alternative involves decommissioning any wells.
Sutton Brook Disposal Area Sf Site
TewksbLfry, Massachusetts
Page 4 of 5
Record of Decision
September 2007
-------
TABLE M-2
ALTERNATIVE LF-2b
ACTION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
State Regulatory Requirements
Soils/Sedlments
Reuse and Disposal of Contaminated Soils at
Massachusetts Landfills (COMM-97 001)
To be considered
This Policy provides information about the Massachusetts
Department of Environmental Protection's requirements,
standards, management practices and approvals for the testing,
tracking, transport, and reuse or disposal of Contaminated Soil at
Massachusetts landfills.
The LF-2b component of the selected remedy will be designed
and implemented to comply with this policy.
Federal Regulatory Requirements
Clean Air Act National Emissions Standards for
Hazardous Air Pollutants (NESHAPs), 40 CFR
Part 61
Applicable
These regulations set standards for emissions of 188 Hazardous
Air Pollutants that are listed in Section 112(b)(1) of the Clean Air
Act.
For the groundwater portion of the LF-2b component of tie
selected remedy, if air stripping is used and any of the 189
hazardous air pollutants are emitted, then LF-2b will comply
with this ARAR.
OSWER Directive 9355.0-28, Air Stripper
Control Guidance, 7/12/89
To be considered
This OSWER directive establishes guidance on the control of air
emissions from air strippers used at Superfund sites for
groundwater treatment
For the groundwater portion of the LF-2b component of the
selected remedy, if air stripping is used, then LF-2b will comply
with this policy.
State Regulatory Requirements
Air
Massachusetts Ambient Air Quality Standards
{310 OMR 6,00)
Applicable
These regulations set primary and secondary standards for
emissions of sulfur oxides, particulate matter, carbon monoxide,
ozone, nitrogen dioxide, and lead.
For the groundwater portion of the LF-2b component of the
selected remedy, if air stripping is used, then LF-2b will comply
with this policy. No air emissions from remedial treatment will
cause ambient air quality standards to be exceeded.
MassDEP Revised Ambient Air Guidelines
(December 6,1995}
To be considered
This document presents MassDEP's revised ambient air
guidelines, presenting the Threshold Effects Exposure Limits
(TELs) and Allowable Ambient Limits (AALs),
The LF-2b component of the selected remedy will be designed
and implemented to comply with this policy.
Massachusetts Air Pollution Control
Regulations (310 CMR 7.00)
Applicable
This regulation stipulates that during construction and/or demolition
activities, air emissions (i.e. dust, particulates, etc.) must be
controlled to prevent air pollution.
Construction activities will be managed to meet the standards
for visible emissions (310 CMR 7.06); dust, odor, construction,
and demolition (310 CMR 7.09); and noise (310 CMR 7.10). If
air stripping is used, then the groundwater portion of the LF-2b
component of the selected remedy will comply with this ARAR.
Odor emissions from the groundwater treatment air stripper
will be controlled with best available control technology.
Sutton Brook Disposal Area Sf Srte
Tewksbury, Massachusetts
Page 5 of 5
Record erf Decision
September 200?
-------
TABLE M-3
ALTERNATIVE LF-2b
LOCATION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Supeifund Site, Tewksbury, Massachusetts
• -'--liQCIltiOrfi.
Summary Requirement -I
• Actions to be Taken to Attain Requirement -
Federal Regulatory Requirements and Guidance
Wetlands Executive Order
(EO11990), 40 CFR 6.302(a),
and 40 CFR Part 6, Appendix
A
Applicable
The Wetlands Executive Order requires federal agencies to avoid
undertaking or providing assistance for new construction located in
wetlands unless there is no practicable alternative and the
proposed action includes all practicable measures to minimize the
destruction, loss, or degradation of wetlands, arid preserve and
enhance natural and beneficial values of wetlands.
Under the LF-2b component of the selected remedy, the installation
of the landfill cover, the construction of a vertical barrier along a
portion of the Southern Lobe, and the installation of wells and
treatment plant for the Southern Lobe groundwater will result in the
unavoidable destruction of existing wetlands. During remedial
design the effects of remedial activities on the wetlands witl be
evaluated and minimized. Compensatory wetlands mitigation will
be performed as necessary to comply with this ARAR,
Surface Water,
Wetlands,
Floodplains
Clean Water Act Section 404
Dredge arid Fill Regulations
(40 CFR 230, 33 CFR 320-323)
Applicable
These regulations outline the requirements for the discharge of
dredged or fill materials into surface waters including wetlands. No
activity that impacts waters of the United States shall be permitted if
a practicable alternative that has less adverse impact on the
aquatic ecosystem exists. If there is no other practicable
alternative, the impacts must be mitigated.
Under the LF-2b component of the selected remedy, the installation
of the landfill cover, the construction of a vertical barrier along a
portion of the Southern Lobe, and the installation of wells and
treatment plant for the Southern Lobe groundwater will result in the
unavoidable destruction of existing wetlands. During remedial
design the effects of remedial activities on the wetlands will be
evaluated and avoided and/or minimized. Compensatory wetlands
mitigation will be performed as necessary to comply with this ARAR.
In addition, brook sediment excavation would be unavoidab e in
order to remediate contaminated sediments. Under the LF-2b
component of the selected remedy, the brook sediments will be
restored with clean sediments. Alternative LF-2b is the least
environmentally damaging practicable alternative that meets the
remedial action objectives.
Floodplains Executive Oraer
(E011988), 40 CFR 6.302(b),
and 40 CFR Part 6, Appendix
A
Applicable
The Floodplains Executive Order requires federal agencies to avoid
impacts associated with the occupancy and modification of a
floodplain unless there is no practicable alternative and the
proposed action includes all practicable measure to reduce the risk
of flood loss, to minimize the impact of floods, and to restore and
preserve the natural and beneficial values of floodplains.
Under the LF-2b component of the selected remedy, available
practicable means will be used to reduce the risk of flood loss, to
minimize the impact of floods, and to restore and preserve the
floodplains. In areas where the landfill cover, vertical barrier, wells
and treatment plant will result in the filling in of areas within the 100-
year floodplain, there will be a replication of 100-year floodplain
space equivalent to the amount loss. Stormwater management
basins will be designed to minimize the impact of floods.
RCRA Floodplain Restrictions
for Hazardous Waste Facilities
(40 CFR 264.16(1}))
Relevant and Appropriate
These regulations require that a hazardous waste facility located in
a 100-year floodplain must be designed, constructed, operated, and
maintained to prevent washout by a 100-year storm.
Under the LF-2b component of the selected remedy, available
practicable means will be used to reduce the risk of flood loss, to
minimize the impact of floods, and to restore and preserve the
floodplains. In areas where the landfill cover, vertical barrier, wells
and treatment plant will result in the filling in of areas within the 100-
year floodplain, there will be a replication of 100-year floodplain
space equivalent to the amount toss. Stormwater management
basins will be designed to minimize the impact of floods. The
landfill cover and any structures will be designed to withstand the
effects of a 100-year storm.
Fish and Wildlife Coordination
Act (16 USC 661 et seq, 40
CFR Part 6)
Applicable
The Fish ar»d Wildlife Coordination Act requires action to protect
fish and wildlife and requires consultation with the U.S. Fish and
Wildlife Service and state wildlife agencies to mitigate losses of fish
and wildlife that result from modification of a water body.
Since the LF-2b component of the selected remedy requires
modification of a water body, when the sediments in Sutton Brook
between the two landfill lobes are excavated, this consultation
requirement will be conducted.
Sutton Brook Disposal Area SF Site
Tewksbury, Massachusetts
Page 1 of 3
Record of Decision
September 2007
-------
TABLE M-3
ALTERNATIVE LF-2b
LOCATION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
TM&ouMmm*
irwilihrijrf«wir --
State Regulatory Requirements
Massachusetts Wetlands
Regulations (310 CMR 10.00;
MGL c. 131, Section 40:
Wetlands Protection Act)
Applicable
These regulations set performance standards for dredging, filling,
and altering of any inland wetland, the buffer zone within 100 feet of
a wetland, and the riverfront area (defined as the area between the
river's mean annual high-water line and a line located 200 feet
away). The requirement also defines wetlands based on vegetation
type and requires that effects on wetlands be mitigated. Resource
areas at the Site covered by the regulations include banks,
bordering vegetated wetlands, land under bodies of water, land
subject to flooding, riverfront and estimated habitats of rare wildlife.
Under this requirement, available alternatives must be considered
that minimize the extent of adverse impacts, and mitigation
including restoration and/or replication is required.
The installation of the lancffill cover, the construction of a vertical
barrier along a portion of the Southern Lobe, and the installation of
wells and treatment plant for the Southern Lobe groundwater will
occur in or around wetlands (and their 100 foot buffer zones) and
Sutton Brook (and its riverfront area). Sediments in Sutton Brook
will be excavated and restored with clean sediments. Because of
the contamination in the landfill source areas, there is no
practicable alternative to installing an impermeable cap and the
other portions of LF-2b, All practicable means will be used to avoid
or minimize harm to the wetlands, including erosion and
sedimentation controls and stormwater management. Wetlands
and sediments unavoidably disturbed by remedial activities will be
mitigated, restored or preserved.
The installation of the landfill cover, the construction of a vertical
Surface Water,
Wetlands,
Floodplains
(Cont'd}
Massachusetts Water Quality
Certification tor Discharge of
Dredged or Fill Material,
Dredging, and Dredging
Material Disposal in Waters of
the U.S. within the
Commonwealth (314 CMR
9.00)
Applicable
For discharges of dredged or fill material: there must be no
practicable alternative with less adverse impact on the aquatic
ecosystem; appropriate and practicable steps must be taken to
avoid and minimize potential adverse impacts to wetlands and land
under water; stormwater discharges must be controlled with BMPs;
and there must not be substantial adverse impacts to the physical,
chemical, or biological integrity of surface waters. For dredging and
dredged material management: there must be no practicable
alternative with less adverse impact on the aquatic ecosystem; arid
if avoidance is not possible then minimize, or if neither avoidance or
minimization are possible, then mitigate potential adverse impacts.
barrier along a portion of the Southern Lobe, and the installation of
wells and treatment plant for the Southern Lobe groundwater will
occur in or around wetlands (and their 100 foot buffer zones) and
Sutton Brook (and its riverfront area). Sediments in Sutton Brook
will be excavated arid restored with clean sediments. Because of
the contamination in the landfill source areas, there is no
practicable alternative to installing an impermeable cap and the
other portions of LF-2b. All practicable means will be used to avoid
or minimize harm to the wetlands, including erosion and
sedimentation controls and stormwater management. Wetlands
and sediments unavoidably disturbed by remedial activities will be
mitigated, restored or preserved. There would be no substantial
long-term adverse impacts to the integrity of surface waters.
Massachusetts Waterways
Regulations (310 CMR 9.00)
Applicable
These regulations set forth criteria for work within flowed and filled
tidelands and other waterways. Waterways concerns focus on the
long term viability of marine uses and protecting public rights in
tidelands, including fishing and access.
Under the LF-2b component of the selected remedy, actions within
waterways at the Site will comply with the regulation's
environmental standards.
Massachusetts Hazardous
Waste Rules, Facility Location
Standards (310 CMR 30.700)
Applicable
These regulations set forth criteria for siting hazardous waste
facilities within Land Subject to Flooding (as defined under the
Massachusetts Wetlands Protection standards); surface water
supplies; and actual, planned, or potential public water supplies
Under the LF-2b component of the selected remedy, any remedial
structures, including the landfills, within Land Subject to Flooding
and potential public water supply area, will be designed,
constructed, operated, and maintained to prevent a release of
hazardous waste within the protected resource area.
Sutton Brook Disposal Area SF Site
Tewksbury, Massachusetts
Page 2 of 3
Record of Decision
September 2007
-------
TABLE M-3
ALTERNATIVE LF-2b
LOCATION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
p.* f~wvm-i yrsviM-.
Other Natural
Resources
Federal Regulatory Requirements |
Endangered Species Act {16
USC 1531 etsea,: 40 CFR
6.302(h); 50 CFR 402)
Applicable if encountered
This statute requires that Federal agencies avoid activities which
jeopardize threatened or endangered species or adversely modify
habitats essential to their survival. Mitigation measures should be
considered if a listed species or habitat may be jeopardized.
No endangered or threatened species have been identified at the
Site to date, if endangered or threatened species in the site area
are identified, remedial activities would avoid actions that would
adversely affect threatened or endangered species or habitats.
National Historic Preservation
Act (16 USC 470 etseq,, 36
CFR 800)
Applicable if encountered
Pursuant to Sections 106 and 110(f) of the NHPA, as amended,
CERCLA response actions are required to take into account the
effects of the response activities on any historic property included or
eligible for inclusion on the National Register of Historic Places,
Should the LF-2b component of the selected remedy impact historic
properties, as determined in the remedial design, activities will be
coordinated with the Massachusetts Historical Commission (MHC).
If it is determined that adverse impacts are unavoidable, then MHC
will be consulted to determine ways to minimize and/or mitigate
such adverse impacts.
State Regulatory Requirements |
Antiquities Act and
Regulations; Massachusetts
Historical Commission;
Protection of Properties
Included in the State Register
of Historic Places (M.6.L. eft.
9, sec. 26-27; 950 CMR 70.00)
Applicable if encountered
These regulations require the adoption of all prudent and feasible
means to eliminate, minimize or mitigate adverse effects to historic
or archaeological properties, and require coordination with the
Massachusetts Historical Commission.
Should the LF-2b component of the selected remedy impact historic
or archaeological properties, as determined in the remedial design,
activities will be coordinated with the Massachusetts Historical
Commission (MHC). If it is determined that adverse impacts cannot
be eliminated, then MHC will be consulted to determine ways to
minimize and/or mitigate such adverse impacts.
Massachusetts Endangered
Species Act, 321 CMR 10.00,
(MGLc. 131 A)
Applicable if encountered
The Commonwealth of Massachusetts has the authority to
research, list, and protect any species deemed endangered,
threatened, or of other special concern. These species are listed
as either endangered, threatened, or species of special concern in
the regulations. Actions must be conducted in a manner that
minimizes the effect on Massachusetts-listed endangered species
and species listed by the Massachusetts Natural Heritage Program
No endangered or threatened species have been identified at the
Site to date. If endangered or threatened species in the site area
are identified, remedial activities would avoid actions that would
adversely affect threatened or endangered species or habitats.
Sutton Brook Disposal Area SF Srte
Tewksbury, Massachusetts
Page 3 of 3
Record of Decision
September 2007
-------
TABLE M-4
ALTERNATIVE FDDA-4
CHEMICAL SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
ma*:-*,i*.
0 3?teriwe*iStatUS if.
¦ Actions to be Taken to AttalrvRaaulrantMit' S -fit ••
Federal Regulatory Requirements
Federal Safe Drinking Water Act
(SDWA) Maximum Contaminant Levels
(MCLs) (40CFR Part 141)
Relevant and appropriate
MCLs are enforceable standards that regulate the
concentration of specific organic and inorganic contaminants
that have been determined to adversely affect human health in
public drinking water supplies. MCLs are relevant and
appropriate for the groundwater at the Site because the
aquifer is a potential source of drinking water.
MCLs were used In determining groundwater preliminary
remediation goals (PRGs) for site contaminants where such
contaminant levels have been established. Under the FDDA-
4 component of the selected remedy, MNA {with a
contingency for active groundwater treatment) will over time
result in the groundwater in the FDDA achieving PRGs.
EPA Risk Reference Doses (RfDs)
To be considered
RfDs are dose levels developed by EPA for use in estimating
the non-carcinogenic risk resutting from exposure to toxic
substances.
RfDs were used to assess health risks due to exposure to non
carcinogenic chemicals in groundwater, and to develop of
acceptable groundwater PRG concentrations. Under the
FDDA-4 component of the selected remedy, MNA {with a
contingency for active groundwater treatment) will over time
result in the groundwater in the FDDA achieving PRGs.
EPA Human Health Assessment Cancer
Slope Factors (CSFs)
To be considered
CSFs are developed by EPA for health effects assessments or
evaluation by the Human Health Assessment Group. These
values present the most up-to-date cancer risk potency
information and are used to compute the individual
incremental cancer risk resulting from exposure to
carcinogens.
CSFs were used to compute the individual cancer risk
resulting from exposure to contaminants tn groundwater, and
in the development of acceptable groundwater PRG
concentrations. Under the FDDA-4 component of the selected
remedy, MNA (with a contingency for active groundwater
treatment) will over time result in the groundwater in the FDDA
achieving PRGs.
Groundwater
Guidelines for Carcinogen Risk
Assessment (EPA/63WP-03/001F,
March 2005)
To be considered
Guidance values were used to evaluate the potential
carcinogenic hazard caused by exposure to contaminants.
Cancer risks identified will be addressed by the FDDA-4
component of the selected remedy.
Supplemental Guidance for Assessing
Susceptibility from Early-life Exposure
to Carcinogens (EPA/630/R-03A303F,
March 2005)
To be considered
Guidance values were used to evaluate the potential
carcinogenic hazard to children caused by exposure to
contaminants.
Child cancer risks identified will be addressed by the FDDA-4
component of the selected remedy.
EPA Office of Water, Drinking Water
Health Advisories EPA 822-R-06-013
To be considered
Health Advisories (HAs) are estimates of acceptable drinking
water levels for chemical substances based on health affects
information; an HA is not a legally enforceable Federal
standard, but serves as technical guidance to assist federal,
state and local officials. HAs were used if constituents did not
have promulgated MCLs.
HAs were used to develop acceptable groundwater PRG
concentrations. Under the FDDA-4 component of the selected
remedy, MNA (with a contingency for active groundwater
treatment) will over time result in the groundwater in the FDDA
achieving PRGs.
State Regulatory Requirements
Massachusetts Groundwater Quality
Standards (314 CMR 6,00)
Applicable
These standards consist of ground water classifications, which
designate and assign the uses for which the various ground
waters of the Commonwealth shall be maintained and
protected; water quality criteria necessary to sustain the
designated uses; and regulations necessary to achieve the
designated uses or maintain the existing ground water quality.
The GWQSs set numeric limits for certain contaminants as
well as a pH range. They were used when they were more
stringent than Federal MCLs.
Groundwater beneath the Site is mapped in a potentially
productive aquifer with the potential (for potable water use.
Under the FDDA-4 component of the selected remedy, MNA
(with a contingency for active groundwater treatment) will over
time result in the groundwater in the FDDA achieving PRGs.
Sutton Brook Oisposal Area SF Site
Tewksbury, Massachusetts
Page 1 of 2
Record c? Decision
September 2007
-------
TABLE M-4
ALTERNATIVE FDDA-4
CHEMICAL SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
ofReaulrament-^^
^Actions tftba Taken to Attaln Requlremarrt
Groundwater
(Cont'd)
Massachusetts Drinking Water
Standards (310 CMR 22.00)
Relevant and appropriate
These standards establish Massachusetts MCLs for organic
and inorganic contaminants that have been determined to
adversely affect human health in public drinking water
systems, The aquifer on-site is not a public water system, but
these requirements are R&A because the aquifer has the
potential to be used as a source of drinking water. These
requirements were used when they were more stringent than
Federal MCLs.
Under the FDDA-4 component of the selected remedy, MNA
(with a contingency for active groundwater treatment) will over
time result in the groundwater in the FDDA achieving PRGs.
Massachusetts DEP Office of Research
and Standards Guidelines (ORSGs)
To be considered
The Massaehusets DEP Office of Research and Standards
issues guidance for chemicals other than those with
Massachusetts MCLs in drinking water. ORSGs are
concentration of chemicals in drinking water, at or below
whit*, adverse health effects are unlikely to occur after
chronic (lifetime) exposure. These guidance values were used
when constituents did not have promulgated MCLs.
Under the FDDA-4 component of the selected remedy, MNA
(with a contingency for active groundwater treatment) will over
time result in the groundwater in the FDDA achieving PRGs.
Soils
Federal Regulatory Requirements
EPA Risk Reference Doses (RfDs)
To he considered
RfDs are dose levels developed by EPA for use in estimating
the non-carcinogenic risk resulting from exposure to toxic
substances.
RfDs were used to assess health risks due to exposure to non
carcinogenic chemicals in soils, and to develop soil cleanup
levels. Under the FDDA-4 component of the selected remedy,
soils with concentrations above the soil cleanup levels will be
excavated to be consolidated with the wastes in the Landfill
Lobes orior to caooirw.
EPA Human Health Assessment Cancer
Slope Factors (CSFs)
To be considered
CSFs are developed by fcHA for health effects assessments or
evaluation by the Human Health Assessment Group. These
values present the most up-to-date cancer risk potency
information and are used to compute the individual
incremental cancer risk resnltino from exnosura to
csi-s were used to compute the individual cancer nsk
resulting from exposure to contaminants In soils, and "in the
development of soil cleanup levels, Under the FDDA-4
component of the selected remedy, soils with concentrations
above the soil riranun levels will he excavated to he
Sutton Qrook Disposal Area SF Site
Tewksbury, Massachusetts
Page 2 of 2
Record of Decision
September 2007
-------
TABLE M-S
ALTERNATIVE FODA-4
ACTION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
Federal Regulatory Requirements
RCRA Subtitle C - Hazardous Waste
Identification arid Listing Regulations (40 CFR
Parts 260-262 and 40 CFR 264,13)
Applicable
Massachusetts has been delegated the authority to administer
these RCRA standards through its state hazardous waste
management regulations. These provisions have been adopted by
the Stale. These regulations include rules to identify hazardous
waste and a requirement to obtain a detailed chemical and
physical analysis of a representative sample of any hazardous
wastes prior to treatment, storage, or disposal.
Because RCRA-type (listed or characteristic! hazardous
wastes were disposed of at the Site during the operation of the
landfill, this requirement was determined to be applicable. Any
media generated as part of monitoring activities and
groundwater extraction and treatment will be tested for
hazardous waste characteristics. If determined to be
hazardous waste, then they will be stored, transported, or
disposed of in accordance with 40 CFR Part 264.
RCRA 40 CFR 264 Subpart 1, Use and
Management of Containers
Applicable if a container is
used in the remedial
action
Massachusetts has been delegated the authority to administer
these RCRA standards through its state hazardous waste
management regulations. These provisions have been adopted by
the State. This regulation establishes requirements for the storage
of containers of hazardous waste.
Because RCRA-type (listed or characteristic) hazardous
wastes were disposed of at the Site during the operation of the
landfill, if the active groundwater treatment contingency is
needed for the FODA-4 component of the selected remedy
and if a container is used to store hazardous waste, then
FODA-4 will be implemented to comply with this ARAR.
Waste
RCRA 40 CFR 284 Subpart J, Tank Systems
Applicable if a tank system
is used in the remedial
action
Massachusetts has been delegated the authority to administer
these RCRA standards through its state hazardous waste
management regulations. These provisions have been adopted by
the State. This regulation establishes requirements for the use of
tank systems for storing or treating hazardous waste.
Because RCRA-type (listed or characteristic) hazardous
wastes were disposed of at the Site during ttie operation of the
landfill, if the active groundwater treatment contingency is
needed for the FDDA-4 component of the selected remedy
and if a tank system is used to store hazardous waste, then
FDDA-4 will be implemented to comply with this AFiAR.
RC RA 40 CFR 264 Subpart L, Waste Piles
Applicable if a waste pile
is used in the remedial
action
Massachusetts has been delegated the authority to administer
these RCRA standards through its state hazardous waste
management regulations. These provisions have been adopted by
the State. This regulation establishes requirements for the use of
piles for storing or treating hazardous waste.
Because RCRA-type (listed or characteristic) hazardous
wastes were disposed of at the Site during the operation of the
landfill, if piles are used to store hazardous waste (potentially
such as the excavated contaminated soils in FDDA prior to
consolidation into the landfill lobes), then the FDDA-4
component of the selected remedy can be implemented to
comply with this ARAR.
RCRA 40 CFR 264 Subpart X, Miscellaneous
Units
Applicable if a
miscellaneous unit is used
in the remedial action
Massachusetts has been delegated the authority to administer
these RCRA standards through its state hazardous waste
management regulations. These provisions have been adopted by
the State. This regulation establishes requirements for the use of
miscellaneous units for treating, storing, or disposing of hazardous
waste.
Because RCRA-type (listed or characteristic) hazardous
wastes were disposed of at the Site during the operation of the
landfill, if the active groundwater treatment contingency Is
needed for the FDOA-4 component of the selected remedy
and if a miscellaneous unit is used to store hazardous waste,
then FDDA-4 will be implemented to comply with this ARAR.
RCRA 40 CFR 264 Subpart AA, Air Emission
Standards for Process Vents
Applicable if a process
vent is used and if
thresholds are met
This regulation establishes air emission standards for process
vents, closed-vent systems, and control devices at hazardous
waste facilities.
tf the active groundwater treatment contingency is needed for
the FDDA-4 component of the selected remedy, if a prooess
vent is used in the remedial action and if applicable thresholds
are met, then air emission controls will be implemented during
groundwater treatment to comply with this regulation.
Sutton Brook Disposal Area SF Site
Tewksbury. Massachusetts
Page 1 of 5
Record c»f Decision
September 200?
-------
TABLE M-S
ALTERNATIVE FDDA-4
ACTION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
a.
RCRA 40 CFR 264 Subpart BB, Air Emission
Standards for Equipment Leaks
Applicable if equipment
covered by this standard
is used and if thresholds
are met
This regulation contains air pollutant emission standards for
equipment teaks at hazardous waste TSO facilities. This subpart
applies to equipment that contains or contacts hazardous wastes
with organic concentrations of at least 10 percent by weight
If the active groundwater treatment contingency is needed for
the FDDA-4 component of the selected remedy and if
equipment covered by this standard is used in the remedial
action and handles hazardous wastes at concentrations that
meet this rule's threshold, then a leak detection and repair
program will be implemented during groundwater treatment to
comply with this regulation.
Waste (cont'd)
RCRA 40 CFR 264 Subpart CC, Air Emission
Standards for Tanks, Surface Impoundments
and Containers
Applicable if a tank or
container is used and if
thresholds are met
This regulation establishes air emission standards for facilities that
treat, store, or dispose hazardous wastes in tanks, surface
impoundments, or containers.
Any media generated as part of monitoring activities and
groundwater treatment (if the contingency is needed) will be
tested for hazardous waste characteristics. If determined to
be hazardous waste, then they will be stored, transported, or
disposed of in accordance with 40 CFR Part 264. If a tank or
container is used in the remedial action and if applicable
thresholds are met, then air emission controls will be
implemented during groundwater treatment to comply with this
regulation.
RCRA 40 CFR 264 Subpart DD, Containment
Buildings
Applicable If a building is
used to house treatment
equipment
This regulation contains design, operating, closure and post-
closure standards and requirements for the storage and treatment
of hazardous waste in containment buildings.
If the active groundwater treatment contingency is needed for
the FDDA-4 component of the selected remedy and if a
building is used to house treatment equipment, then the
design, operation, closure, and post-closure of the treatment
building for FDDA-4 will comply with this regulation.
Federal Regulatory Requirements
Clean Water Act Section 402 National
Pollutant Discharge Elimination System
(NPDES) (40 CFR Part 122-125 and 131)
Applicable
This act and regulations establish discharge limitations, monitoring
requirements, and best management practices. Point-source
discharges of effluent to surface water must comply with NPDES
requirements (e.g., federal and state ambient water quality criteria
(AWQC)).
If the active groundwater treatment contingency is needed for
the FDDA-4 component of the selected remedy, on-site
discharges to surface waters, including Sutton Brook and
adjacent wetlands, shall meet these substantive discharge
standards. These discharge limitations shall also be used to
develop monitoring standards for surface waters.
Surface Water
Clean Water Act (CWA) Ambient Water Quality
Criteria (AWQC) (33 USC 1251 etseq.) (40
CFR 122.44)
Relevant and appropriate
Federal AWQC are recommended (non-enforceable) criteria
published by EPA and provided to the States. AWQC are listed for
protection of ecological and human health for approximately 160
contaminants. AWQC are used in establishing State water quality
standards.
If the active groundwater treatment contingency is needed for
the FDDA-4 component of the selected remedy and if treated
groundwater is discharged to surface water, it will be treated
as needed to comply with State water quality standards based
on AWQC. Surface water monitoring will be performed.
These standards will be used to help assess the effectiveness
of the groundwater treatment
Clean Water Act (CWA) Pretreatment
Regulations for Discharges to a POTW (40
CFR Part 403
Applicable if treated
groundwater is discharged
to the POTW
These regulations prohibit the introduction of pollutants into a
publicly owned treatment works (POTW) and has pretreatment
requirements for sources to a POTW
If the active groundwater treatment contingency is needed for
the FDDA-4 component of the selected remedy and if treated
groundwater is discharged to the local POTW, it will be treated
as need to comply with these pretreatment requirements.
State Regulatory Requirements
Mass. Clean Waters Act - MassDEP Surface
Water Discharge Permit Program (314 CMR
3.00; MGL c. 21 Sections 26-53)
Applicable
This act and program establish the requirements Intended to
maintain the quality of surface waters by controlling the direct
discharge of pollutants to surface waters. Direct discharge of
wastewater to surface waters must meet effluent discharge limits
established by this program.
If the active groundwater treatment contingency is needed for
the FDDA-4 component of the selected remedy, on-site
discharges to surface waters, including Sutton Brook and
adjacent wetlands, shall meet these substantive discharge
standards. These discharge limitations shall also be used to
develop monitoring standards for surface waters.
Sutton Brook Disposal Area SF Site
Tewksbjry, Massachusetts
Page 2 of 5
Record of Decision
September 200?
-------
TABLE M-5
ALTERNATIVE FDDA-4
ACTION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
-/Madia :i'is
dMMfi&'StabN -r, ¦¦¦mi
Massachusetts Surface Water Quality
Standards (314 CMR 4.00)
Applicable
The Massachusetts Surface Water Quality Standards designate
the most sensitive uses for which the various waters of the
Commonwealth shall be enhanced, maintained and protected;
which prescribe the minimum water quality criteria required to
sustain the designated uses; and which contain regulations
necessary to achieve the designated uses and maintain existing
water quality including, where appropriate, the prohibition of
discharges. These regulations limit or prohibit discharges of
pollutants to surface waters to ensure that the surface water quality
standards of the receiving waters are protected and maintained or
attained.
If the active groundwater treatment contingency is needed for
the FDDA-4 component of the selected remedy, on-site
discharges to surface waters, including Sutton Brook and
adjacent wetlands, shall meet these substantive discharge
standards. These discharge limitations shall also be used to
develop monitoring standards for surface waters.
Surface Water
(Cont'd)
MassDEP Surface Water Discharge Permit
Program (314 CMR 3.00)
Applicable
These regulations are intended to protect surface water bodies in
the Commonwealth by regulating the discharge Into them. Direct
discharges of wastewater to surface waters must meet effluent
discharge limits established by this program.
If the active groundwater treatment contingency is needed for
the FDDA-4 component of the selected remedy, on-site
discharges to surface waters, including Sutton Brook and
adjacent wetlands, shall meet these substantive discharge
standards. These discharge limitations shad also be used to
develop monitorincj standards for surface waters.
Massachusetts Pretreatment Standards for
Discharges to Wastewater Treatment Works
(314 CMR 12.00)
Applicable
These regulations prohibit the introduction of pollutants into a
publicly owned treatment works (POTW) and has pretreatment
requirements for sources to a POTW
If the active groundwater treatment contingency is needed for
the FDDA-4 component of the selected remedy and if treated
groundwater is discharged to the local POTW, it will be treated
as need to comply with these pretreatment requirements.
MassDEP Stormwater Management Policy
To be considered
The goal of the policy is to improve water quality and address
water quantity problems within Massachusetts through the
implementation of performance standards for stormwater
manaqement.
The FDDA-4 component of the selected remedy will be
designed and implemented to comply with this requirement.
Federal Regulatory Requirements
RCRA Subtitfe C - Releases from Solid Waste
Management Units (40 CFR Subpart F,
264.95 and 264.96(a) and (c))
Applicable
These regulations identify specific monitoring requirements
applicable to hazardous waste facilities, including specifying the
point of compliance at which the groundwater protection standards
apply and at which monitoring must he conducted, as well as
specifying the compliance period during which the groundwater
protection standard applies.
The FDDA-4 component of the selected remedy will be
implemented to comply with these requirements. Because
EPA has determined that the point of compliance at which the
groundwater protection standards apply is the edge of the
waste management unit (the landfill lobes), these standards
will be met throughout the FDDA.
Groundwater
Underground Injection (40 CFR Part 144)
Relevant and appropriate
These regulations provide regulatory compliance standards for
treatment facilities that inject wastes underground. The use at
wells lo dispose of hazardous waste is prohibited.
If the active groundwater treatment contingency is needed far
the FDDA-4 component of the selected remedy arid if the
performance of the FDDA-4 component of the selected
remedy utilizes underground injection for the treated
groundwater or uses an infiltration gallery or any other system
that disposes of treatment water or waste into groundwater as
the remediation technology, groundwater will be treated to be
non-hazardous prior to subsurface discharge.
Sutton Brook Disposal Area SF Site
Tewksbury, Massachusetts
Page 3 of &
Record of Decision
September 2007
-------
TABLE M-S
ALTERNATIVE FDDA-4
ACTION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
»< v icwtoiW I!—itiHif Rwiuliwiiei* s*v- •sp*# '#*¦#
Final OSWER Directive "Use of Monitored
Natural Attenuation at Superfund, RCRA
Corrective Action, arid Underground Storage
Tank Sites {OSWER Dir. 9200.4-17P, 4/12/99)
To be considered
This guidance sets criteria for evaluating monitored natural
attenuation as a remedy at, among others, Superfund sites.
For the FDDA-4 component of the selected remedy, monitored
natural attenuation was determined to be appropriate in
accordance with this TBC. Under FDDA-4, contaminant levels
in the groundwater plume underneath FDDA will be monitored
consistent with this guidance. Active groundwater treatment is
retained as a contingency if determined to be necessary as
described in Part 2 of the ROD.
State Regulatory Requirements
Groundwater
(Cont'd)
MassDEP Underground Injection Control
Regulations (310 OMR 27.00)
Applicable
These regulations are intended to protect underground sources of
drinking water by regulating the underground injection of
hazardous wastes, fluids used for extraction of minerals, oil, and
energy, and any other fluids having potential to contaminate
groundwater.
If the active groundwater treatment contingency is needed for
the FDDA-4 component of the selected remedy and if the
performance of the FDDA-4 component of the selected
remedy utilizes underground injection for the treated
groundwater or uses an infiltration gallery or any other system
that disposes of treatment water or waste into groundwater as
the remediation technology, groundwater will be treated to be
non-hazardous prior to subsurface discharge.
MassDEP Groundwater Discharge Permit
Program (314 CMR 5.00)
Applicable
These regulations are intended to protect groundwater quality by
controlling the discharge of pollutants to the ground waters of the
Commonwealth to assure that these waters are protected for their
highest potential use, These regulations set effluent limits for the
discharge of pollutants to groundwater.
If the active groundwater treatment contingency is needed for
the FDDA-4 component of the selected remedy and if this
contingent remedy utilizes underground injection, infiltration
gallery or any other system that disposes of treatment water or
waste into groundwater as the remediation technology,
groundwater will be treated to meet the substantive
requirements of these regulations prior to subsurface
discharge.
Massachusetts Well Decommissioning
Requirements (313 CMR 3.03)
Applicable
These regulations provide for certain notification requirements
upon well abandonment
These regulations will be followed to the extent that the
alternative involves decommissioning any wells.
Federal Regulatory Requirements
Clean Air Act National Emissions Standards for
Hazardous Air Pollutants (NESHAPs), 40 CFR
Part 61
Applicable
These regulations set standards for emissions of 1H9 Hazardous
Air Pollutants that are listed in Section 112(b)(1) of the Clean Air
Act.
If the active groundwater treatment contingency is needed for
the FDDA-4 component of the selected remedy and if air
stripping is used and any of the 189 hazardous air pollutants
are emitted, then FDDA-4 will comply with this ARAR.
Air
OSWER Directive 93SS.0-23, Air Stripper
Control Guidance, 7/12/89
To be considered
This OSWER directive establishes guidance on the control of air
emissions from air strippers used at Superfund sites for
groundwater treatment
If the active groundwater treatment contingency is needed for
the FDDA-4 component of the selected remedy and if air
stripping is used, then FDDA-4 will comply with this policy.
State Regulatory Requirements
Massachusetts Ambient Air Quality Standards
(310 CMR 6.00)
Applicable
These regulations set primary and secondary standards for
emissions of sulfur oxides, particulate matter, carbon monoxide,
ozone, nitrogen dioxide, and lead.
If the active groundwater treatment contingency is needed for
the FDDA-4 component of the selected remedy and if air
stripping is used, then FDDA-4 will comply with this policy. No
air emissions from remedial treatment will cause ambient air
quality standards to be exceeded.
Sutton Brook Disposal Area SF Site
Tewksbury, Massachusetts
Page 4 of 5
Record of Decision
September 2007
-------
TABLE M-5
ALTERNATIVE FDDA-4
ACTION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
6*6$SltedfcVe!h;i
T '.a* « ¦ RfifcjpflUCfcnent' £SjTX'. 4
MassDEP Revised Ambient Air Guidelines
(December 6,1995)
To be considered
This document presents MassDEP's revised ambient air
guidelines, presenting the Threshold Effects Exposure Limits
(TELs) and Allowable Ambient Limits (AALs).
The FDDA-4 component of the selected remedy will be
designed and implemented to comply with this policy.
Air (Cont'd)
Massachusetts Air Pollution Control
Regulations (310 CMR 7,00)
Applicable
This regulation stipulates that during construction and/or demolition
activities, air emissions (i.e. dust, particulates, etc.) must be
controlled to prevent air pollution.
Construction activities will be managed to meet the standards
for visible emissions (310 CMR 7.06); dust, odor, construction,
and demolition (310 CMR 7.09); and noise (310 CMR 7.10). If
the active groundwater treatment contingency is needed for
the FDDA-4 component of the selected remedy and if air
stripping is used, then FDDA-4 will comply with this ARAR
Odor emissions from the groundwater treatment air stripper
will be controlled with best available control technology.
Sutton Brook Disposal Area SF Site
Tewksbury, Massachusetts
Page 5 erf 5
Record of Decision
September 2007
-------
TABLE M-6
ALTERNATIVE FDDA-4
LOCATION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
location
Federal Regulatory Requirements and Guidance
Wetlands Executive Order
(EQ11990), 40 CFR 6.302(a),
and 40 CFR Part 6, Appendix
A
Applicable
The Wetlands Executive Order requires federal agencies to avoid
undertaking or providing assistance for new construction located in
wetlands unless there is no practicable alternative and the
proposed action includes all practicable measures to minimize the
destruction, loss, or degradation of wetlands, and preserve and
enhance natural and beneficial values of wetlands.
Under the FDDA-4 component of the selected remedy, the
excavation of contaminated soil areas and the installation of wells
and possible treatment plant (if the active groundwater treatment
contingency is needed) will occur close to delineated wetland
boundaries and potentially may disturb some areas. Because of the
contamination in soils in the FDDA, there is no practicable
alternative to the excavation of these contaminated soils for
consolidation with the Landfill Lobes prior to capping. Similarly, if
the active groundwater treatment contingency is needed, wetlands
may be unavoidably impacted. During remedial design, the effects
of remedial activities on the wetlands will be evaluated and
minimized. Compensatory wetlands mitigation would be performed
as necessary to comply with this ARAR.
Surface Water,
Wetlands,
Floodplains
Clean Water Act Section 404
Dredge and Fill Regulations
(40 CFR 230, 33 CFR 320-323)
Applicable
These regulations outline the requirements for the discharge of
dredged or fill materials into surface waters including wetlands. No
activity that impacts waters of the United States shall be permitted if
a practicable alternative that has less adverse impact on the
aquatic ecosystem exists. If there is no other practicable
alternative, the impacts must be mitigated.
Under the FDDA-4 component of the selected remedy, the
excavation of contaminated soil areas and the installation of wells
and possible treatment plant (if the active groundwater treatment
contingency is needed) will occur close to delineated wetland
boundaries and potentially may disturb some areas. Because of the
contamination in soils in the FDDA, there is no practicable
alternative to the excavation of these contaminated soils far
consolidation with the Landfill Lobes prior to capping. Similarly, if
the active groundwater treatment contingency is needed, wetlands
may be unavoidably impacted. During remedial design, the effects
of remedial activities on the wetlands will be evaluated and avoided
and/or minimized. Compensatory wetlands mitigation would be
performed as necessary to comply with this ARAR. Alternative FDD
4 is the least environmentally damaging practicable alternative that
meets the remedial action objectives.
Floodplains Executive Order
(E011988), 40 CFR 6.302(b),
and 40 CFR Part 6, Appendix
A
Applicable
The Floodplains Executive Order requires federal agencies to avoid
impacts associated with the occupancy and modification of a
floodplain unless there is no practicable alternative and the
proposed action includes all practicable measure to reduce the risk
of flood loss, to minimize the impact of floods, and to restore and
preserve the natural and beneficial values of floodplains.
Under the FDDA-4 component of the selected remedy, available
practicable means will be used to reduce the risk of flood loss, to
minimize the impact of floods, and to restore and preserve the
floodplains.
Sutton Brook Disposal Area SF Site
Tewksbury, Massachusetts
Page 1 of 4
Record of Decision
September 2007
-------
TABLE M-6
ALTERNATIVE FDDA-4
LOCATION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
RCRA Floodplain Restrictions
for Hazardous Waste Facilities
(40 CFR 264.18(b))
Relevant and Appropriate
These regulations require that a hazardous waste facility located in
a 100-year floodplain must be designed, constructed, operated, and
maintained to prevent washout by a 100-year storm.
Under the FDDA-4 component of the selected remedy, any
hazardous waste facility, including the the contingent remedy's
possible treatment plant, will be designed, constructed, operated,
and maintained with all available practicable means to reduce the
risk of flood loss, to minimize the impact of floods, and to restore
and preserve the fioodplains. In areas where the treatment plant will
result in the filling in of areas within the 100-year floodplain, there
will be a replication of 100-year floodplain space equivalent to the
amount loss. Stormwater management basins will be designed to
minimize the impact of floods. Any structures will be designed to
withstand the effects of a 100-year storm.
State Regulatory Requirements
Surface Water,
Wetlands,
Fioodplains
(Cont'd)
Massachusetts Wetlands
Regulations (310 CMR 10.00;
MGLc. 131, Section 40:
Wetlands Protection Act)
Applicable
These regulations set performance standards for dredging, filling,
and altering of any inland wetland, the buffer zone within 100 feet of
a wetland, and the riverfront area (defined as the area between the
river's mean annua! high-water line and a line located 200 feet
away). The requirement also defines wetlands based on vegetation
type and requires that effects on wetlands be mitigated. Resource
areas at the Site covered by the regulations include banks,
bordering vegetated wetlands, land under bodies of water, land
subject to flooding, riverfront and estimated habitats of rare wildlife.
Under this requirement, available alternatives must be considered
that minimize the extent of adverse impacts, and mitigation
including restoration and/or replication is required.
Under the FDDA-4 component of the selected remedy, the
excavation of contaminated soils and the installation of wells and
possible treatment plant (if the active groundwater treatment
contingency is needed) will occur within the 100 foot buffer zone of
wetlands. Because of the contamination in soils in the FDDA, there
is no practicable alternative to the excavation of these
contaminated soils for consolidation with the Landfill Lobes prior to
capping. Similarly, if the active groundwater treatment contingency
is needed, wetlands may be unavoidably impacted. All practicable
means will be used to avoid or minimize harm to the wetland buffer
zone, including erosion and sedimentation controls and stormwater
management. The wetland buffer zone area unavoidably disturbed
by remedial activities will be mitigated, restored or preserved.
Massachusetts Water Quality
Certification for Discharge of
Dredged or Fill Material,
Dredging, and Dredging
Material Disposal in Waters of
the U.S. within the
Commonwealth (314 CMR
9.00)
Applicable
For discharges of dTedged or fill material: there must be no
practicable alternative with less adverse impact on the aquatic
ecosystem; appropriate and practicable steps must be taken to
avoid and minimize potential adverse impacts to wetlands and land
underwater; stormwater discharges must be controlled with BMPs;
and there must not be substantial adverse impacts to the physical,
chemical, or biological integrity of surface waters. For dredging and
dredged material management: there must be no practicable
alternative with less adverse impact on the aquatic ecosystem; and
if avoidance is not possible then minimize, or if neither avoidance or
minimization are possible, then mitigate potential adverse impacts.
Under the FDDA-4 component of the selected remedy, the
excavation of contaminated soils and the installation of wells and
possible treatment plant (if the active groundwater treatment
contingency is needed) will occur within the 100 foot buffer zone of
wetlands. Because of the contamination in soils in the FDDA, there
is no practicable alternative to the excavation of these
contaminated soils for consolidation with the Landfill Lobes prior to
capping. Similarly, if the active groundwater treatment contingency
is needed, wetlands may be unavoidably impacted. All practicable
means will be used to avoid or minimize harm to the wetland buffer
zone, including erosion and sedimentation controls and stormwater
management. The wetland buffer zone area unavoidably disturbed
by remedial activities will be mitigated, restored or preserved.
There would be no substantial long-term adverse impacts to the
integrity of surface waters.
Sutton Brook Disposal Area ST Site
Tewksbu^, Massachusetts
Page 2 of 4
Hecorti crt Decision
September 2007
-------
TABLE M-€
ALTERNATIVE FDDA-4
LOCATION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
Surface Water,
Wetlands,
Floodplains
{Cont'd)
Massachusetts Waterways
Regulations (310 CMR 9.00)
Applicable
These regulations set forth criteria for worts within flowed and filled
tidelands and other waterways. Waterways concerns focus on the
long term viability of marine uses and protecting public rights in
tidelands, including fishing and access.
Under the FDDA-4 component of the selected remedy, the
excavation of contaminated soil areas and the installation of wells
and possible treatment plant (if the active groundwater treatment
contingency is needed) will occur close to delineated wetland
boundaries and potentially may disturb some areas. Because of the
contamination in soils in the FDDA, there is no practicable
alternative to the excavation of these contaminated soils for
consolidation with the Landfill Lobes prior to capping. Similarly, if
the active groundwater treatment contingency is needed, wetlands
may be unavoidably impacted. During remedial design, the effects
of remedial activities on the wetlands will be evaluated and avoided
and/or minimized. Compensatory wetlands mitigation would be
performed as necessary to comply with this ARAR.
Massachusetts Hazardous
Waste Rules, Facility Location
Standards (310 CMR 30,700}
Applicable
These regulations set forth criteria for siting hazardous waste
facilities within Land Subject to Flooding {as defined under the
Massachusetts Wetlands Protection standards); surface water
supplies; and actual, planned, or potential public water supplies
Under the FDDA-4 component of the selected remedy, any
hazardous waste facility, including the the contingent remedy's
possible treatment plant, within Land Subject to Flooding and
potential public water supply area, will be designed, constructed,
operated, and maintained to prevent a release of hazardous waste
within the protected resource area.
Federal Regulatory Requirements
Endangered Species Act (16
USC 1531 et sea.: 40 CFR
6.302(h); 50 CFR 402)
Applicable if encountered
This statute requires that Federal agencies avoid activities which
jeopardize threatened or endangered species or adversely modify
habitats essential to their survival. Mitigation measures should be
considered if a listed species or habitat may be jeopardized.
No endangered or threatened species have been identified at the
Site to date. If endangered or threatened species in the site area
are identified, remedial activities would avoid actions that would
adversely affect threatened or endangered species or habitats.
Other Natural
Resources
National Historic Preservation
Act (16 USC 470 et seq., 36
CFR 800)
Applicable if encountered
Pursuant to Sections 106 and 110(f) of the NHPA, as amended,
CERCLA response actions are required to take into account the
effects of the response activities on any historic property included or
eligible for inclusion on the National Register of Historic Places.
Should the FDDA-4 component of the selected remedy impact
historic properties, as determined in the remedial design, activities
will be coordinated with the Massachusetts Historical Commission
(MHC), If it is determined that adverse impacts are unavoidable,
then MHC will be consulted to determine ways to minimize and/or
mitigate such adverse impacts.
State Regulatory Requirements
Antiquities Act and
Regulations; Massachusetts
Historical Commission;
Protection of Properties
Included in the State Register
of Historic Places (M.G.L. ch.
9, sec. 26-27; 950 CMR 70,00)
Applicable if encountered
These regulations require the adoption of all prudent and feasible
means to eliminate, minimize or mitigate adverse effects to historic
or archaeological properties, and require coordination with the
Massachusetts Historical Commission.
Should the FDDA-4 component of the selected remedy impact
historic or archaeological properties, as determined in the remedial
design, activities will be coordinated with the Massachusetts
Historical Commission (MHC). If it is determined that adverse
impacts cannot be eliminated, ttien MHC will be consulted to
determine ways to minimize and/or mitigate such adverse impacts.
Sutton Brook Disposal Area SF Site
Tewksbury, Massachusetts
Page 3 of 4
Record of Decision
September 20G7
-------
TABLE M-6
ALTERNATIVE FDDA-4
LOCATION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
Other Natural
Resources (Cont'd)
Massachusetts Endangered
Species Act, 321 CMR 10.00,
(MGLc. 131A)
Applicable if encountered
The Commonwealth of Massachusetts has the authority to
research, list, and protect any species deemed endangered,
threatened, or of other special concern. These species are listed
as either endangered, threatened, or species of special concern in
the regulations. Actions must be conducted in a manner that
minimizes tie effect on Massachusetts-listed endangered species
and species listed by the Massachusetts Natural Heritage Program.
No endangered or threatened species have been identified at the
Site to date. If endangered or threatened species in the site area
are identified, remedial activities would avoid actions that would
adversely affect threatened or endangered species or habitats.
Sutton Brook Disposal Area SF Site
Tewksbury, Massachusetts
Page A of 4
Record of Decision
September 200?
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TABLE M-7
ALTERNATIVE GSA-2
CHEMICAL SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
Federal Regulatory Requirements
Soils
EPA Human Health Assessment Cancer
Slope Factors (CSFs)
To be considered
CSFs are developed by EPA for health effects assessments or
evaluation by the Human Health Assessment Group. These
values present the most up-to-date cancer risk potency
information and are used to compute the individual
incremental cancer risk resulting from exposure to
carcinogens.
CSFs were used to compute the individual cancer risk
resulting from exposure to contaminants in soils, and in the
development of soil cleanup levels. Under the GSA-2
component of the selected remedy, soils with concentrations
above the soil cleanup levels will be excavated to be
consolidated with ttie wastes in the Landfill Lobes prior to
capping.
Sutton BrDOk Disposal Area SF Site
Tewkstxiry. Massachusetts
Page 1 of 1
Record of Decisksr.
September 2007
-------
TABLE M-8
ALTERNATIVE GSA-2
ACTION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
Federal Regulatory Requirements
Waste
RCRA Subtitle C - Hazardous Waste
Identification and Listing Regulations (40 CFR
Parts 260-262 and 40 CFR 264,13)
Applicable
Massachusetts has been delegated the authority to administer
these RCRA standards through its state hazardous waste
management regulations. These provisions have been adopted by
the State, These regulations include rules to identify hazardous
waste and a requirement to obtain a detailed chemical and
physical analysis of a representative sample of any hazardous
wastes prior to treatment, storage, or disposal.
Because RCRA-type (listed or characteristic) hazardous
wastes were disposed of at the Site during the operation of the
landfill, this requirement was determined to be applicable. Any
media generated as part of monitoring activities will be tested
for hazardous waste characteristics. If determined to be
hazardous waste, then they will be stored, transported, or
disposed of in accordance with 40 CFR Part 264.
RCRA 40 CFR 264 Subpart L, Waste Piles
Applicable ir a waste pile
is used in the remedial
action
Massachusetts has been delegated the authority to administer
these RCRA standards through its state hazardous waste
management regulations. These provisions have been adopted by
the State. This regulation establishes requirements for the use of
piles for storing or treating hazardous waste.
Because RCRA-type (listed or characteristic) hazardous
wastes were disposed of at the Site during the operation of the
landfill, if piles are used to store hazardous waste (potentially
such as the excavated contaminated soils in GSA prior to
consolidation into the landfill lobes), then the FDDA-4
component of tfie selected remedy can be implemented to
comply with this ARAR.
Surface Water
MassDEP Stormwater Management Policy
To be considered
The goal of the policy is to improve water quality and address
water quantity problems within Massachusetts through the
implementation of performance standards for stormwater
mananement.
The GSA-2 component of the selected remedy will be
designed and implemented to comply with this requirement.
Air
Massachusetts Air Pollution Control
Regulations (310 CMR 7.00)
Applicable
This regulation stipulates that during construction and/or demolition
activities, air emissions (i.e. dust, particulates, etc.) must be
controlled to prevent air pollution.
Construction activities will be managed to meet the standards
for visible emissions (310 CMR 7.06); dust, odor, construction,
and demolition (310 CMR 7.09); and noise (310 CMR 7.10).
Sutton Brook Disposal Area SF Site
Tewksbury, Massachusetts
Page 1 of 1
Record of Decision
September 2007
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TABLE M-9
ALTERNATIVE GSA-2
LOCATION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
ix:v*
SBEc
SUSJiStatriitiMiv. i
Requirement
Federal Regulatory Requirements and Guidance
Wetlands Executive Order
(EO11990), 40 CFR 6.302(a),
and 40 CFR Part 6, Appendix
A
Applicable
The Wetlands Executive Order requires federal agencies to avoid
undertaking or providing assistance for new construction located in
wetlands unless there is no practicable alternative and the
proposed action includes all practicable measures to minimize the
destruction, toss, or degradation of wetlands, and preserve and
enhance natural and beneficial values of wetlands.
Under the GSA-2 component of the selected remedy, the
excavation of contaminated soil areas will occur near but outside
delineated wetland boundaries. During remedial design the effects
of remedial activities on the wetlands will be evaluated and avoided
and/or minimized. Compensatory wetlands mitigation will be
performed as necessary to comply with this ARAR for those
unavoidable minimal impacts. Alternative GSA-2 is the least
environmentally damaging practicable alternative that meets the
remedial action objectives.
Clean Water Act Section 404
Dredge and Fill Regulations
(40 CFR 230, 33 CFR 320-323)
Applicable
These regulations outline the requirements for the discharge of
dredged or fill materials into surface waters including wetlands. No
activity that impacts waters of the United States shall be permitted if
a practicable alternative that has less adverse impact exists. If
there is no other practicable alternative, the impacts must be
mitigated.
Under the GSA-2 component of the selected remedy, the
excavation of contaminated soil areas will occur near but outside
delineated wetland boundaries. During remedial design the effects
of remedial activities on the wetlands will be evaluated and
minimized. Compensatory wetlands mitigation will be performed as
necessary to comply with this ARAR for those unavoidable minimal
impacts.
Surface Water,
Wetlands,
Ftoodplains
Ftoodplains Executive Order
(E011988), 40 CFR 6.302(b),
and 40 CFR Part 6, Appendix
A
Applicable
The Floodplains Executive Order requires federal agencies to avoid
impacts associated with the occupancy and modification of a
floodplain unless there is no practicable alternative and the
proposed action includes all practicable measure to reduce the risk
of flood loss, to minimize the impact of floods, and to restore and
preserve the natural and beneficial values of ftoodplains.
Under the GSA-2 component of the selected remedy, available
practicable means will be used to reduce the risk of flood loss, to
minimize the impact of floods, and to restore and preserve the
floodplains.
State Regulatory Requirements
Massachusetts Wetlands
Regulations {310 CMR 10.00;
MGL a 131, Section 40:
Wetlands Protection Act)
Applicable
These regulations set performance standards for dredging, filling,
and altering of any inland wetland, the buffer zone within 100 feet of
a wetland, and the riverfront area (defined as the area between the
river's mean annual high-water line arid a tine located 200 feet
away). The requirement also defines wetlands based on vegetation
type and requires that effects on wetlands be mitigated. Resource
areas at the Site covered by the regulations include banks,
bordering vegetated wetlands, land under bodies of water, land
subject to flooding, riverfront and estimated habitats of rare wildlife.
Under this requirement, available alternatives must be considered
that minimize the extent of adverse impacts, and mitigation
including restoration and/or replication is required.
Under the GSA component of the selected remedy, some of the
excavation of contaminated soils may occur within the 100 foot
buffer zone of wetlands. Because of the contamination in soils in
the GSA, there is no practicable alternative to the excavation of
these contaminated soils for consolidation with the Landfill Lobes
prior to capping. All practicable means will be used to avoid or
minimize harm to the wetland buffer zone, including erosion and
sedimentation controls and stormwater management. The wetland
buffer zone area unavoidably disturbed by remedial activities will be
mitigated, restored or preserved.
Sutton Brook Disposal Area SF Site
Tewksbury, Massachusetts
Page 1 of 2
Rectrt of Decision
September 2007
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TABLE M-9
ALTERNATIVE GSA-2
LOCATION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, TewKsbury, Massachusetts
Surface Water,
Wetlands,
Flood plains
(Cont'd)
Massachusetts Water Quality
Certification for Discharge of
Dredged or Fill Material,
Dredging, and Dredging
Material Disposal in Waters of
the U.S. within the
Commonwealth (314 CMR
9.00)
Applicable
For discharges of dredged or fill material: there must be no
practicable alternative with less adverse impact on the aquatic
ecosystem; appropriate and practicable steps must be taken to
avoid and minimize potential adverse impacts to wetlands and land
under water; storm water discharges must be controlled with BMPs;
and there must not be substantial adverse impacts to the physical,
chemical, or biological integrity of surface waters. For dredging and
dredged material management there must be no practicable
alternative witti less adverse impact on the aquatic ecosystem; and
if avoidance is not possible then minimize, or if neither avoidance or
minimization are possible, then mitigate potential adverse impacts.
Under the GSA component of the selected remedy, some of the
excavation of contaminated soils may occur within the 100 foot
buffer zone of wetlands. Because of the contamination in soils in
the GSA, there is no practicable alternative to the excavation of
these contaminated soils for consolidation with the Landfill Lobes
prior to capping. All practicable means will be used to avoid or
minimize harm to the wetland buffer zone, including erosion and
sedimentation controls and storrnwater management. The wetland
buffer zone area unavoidably disturbed by remedial activities will be
mitigated, restored or preserved. There would be no substantial
long-term adverse impacts to the integrity of surface waters.
Massachusetts Waterways
Regulations (310 CMR 9.00)
Applicable
These regulations set forth criteria for work within flowed and filled
tidelands and other waterways. Waterways concerns focus on the
long term viability of marine uses and protecting public rights in
tidelands, including fishing and access.
Under the GSA-2 component of the selected remedy, the
excavation of contaminated soil areas will occur near but outside
delineated wetland boundaries. During remedial design the effects
of remedial activities on the wetlands will be evaluated and avoided
and/or minimized. Compensatory wetlands mitigation will be
performed as necessary to comply with this ARAR for those
unavoidable minimal impacts.
Federal Regulatory Requirements
Endangered Species Act (16
USC 1531 et sea.: 40 CFR
6.302(h); 50 CFR 402)
Applicable if encountered
This statute requires (hat Federal agencies avoid activities which
jeopardize threatened or endangered species or adversely modify
habitats essential to their survival. Mitigation measures should be
considered if a listed species or habitat may be jeopardized.
No endangered or threatened species have been identified at the
Site to date. If endangered or threatened species in the site area
are identified, remedial activities would avoid actions that would
adversely affect threatened or endangered species or habitats.
National Historic Preservation
Act {16 USC 470 etseq., 36
CFR 800)
Applicable if encountered
Pursuant to Sections 106 and 110(f) of the NHPA, as amended,
CERCLA response actions are required to take into account the
effects of the response activities on any historic property included or
eligible for inclusion on the National Register of Historic Places.
Should the GSA-2 component of the selected remedy impact
historic properties, as determined in the remedial design, activities
will be coordinated with the Massachusetts Historical Commission
(MHC). If it is determined that adverse impacts are unavoidable,
then MHC will be consulted to determine ways to minimize and/or
mitigate such adverse impacts.
State Regulatory Requirements
Other Natural
Resources
Antiquities Act and
Regulations; Massachusetts
Historical Commission;
Protection of Properties
Included in the State Register
of Historic Places (M.G.L. ch.
9, sec. 26-27; 950 CMR 70.00)
Applicable if encountered
These regulations require the adoption of all prudent and feasible
means to eliminate, minimize or mitigate adverse effects to historic
or archaeological properties, and require coordination with the
Massachusetts Historical Commission,
Should the GSA-2 component of (he selected remedy impact
historic or archaeological properties, as determined in the remedial
design, activities will be coordinated with the Massachusetts
Historical Commission (MHC). If it is determined that adverse
impacts cannot be eliminated, then MHC will be consulted to
determine ways to minimize and/or mitigate such adverse impacts.
Massachusetts Endangered
Species Act, 321 CMR 10.00,
(MGLc. 131A)
Applicable if encountered
The Commonwealth of Massachusetts has the authority to
research, list, and protect any species deemed endangered,
threatened, or of other special concern. These species are listed
as either endangered, threatened, or species of special concern in
the regulations. Actions must be conducted in a manner that
minimizes the effect on Massachusetts-listed endangered species
and species listed by the Massachusetts Natural Heritage Program.
No endangered or threatened species have been identified at the
Site to date. If endangered or threatened species in the site area
are identified, remedial activities would avoid actions that would
adversely affect threatened or endangered species or habitats.
Sutton Brook Disposal Area SF Site
TewksbufV. Massachusetts
Page 2 of 2
Record of Decision
September 2007
-------
TABLE M-10
ALTERNATIVE DGGW-2
CHEMICAL SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
XiX'AttaIn
Federal Regulatory Requirements
Federal Safe Drinking Water Act
(SDWA) Maximum Contaminant Levels
(MCLs) (40 CFR Part 141)
Relevant and appropriate
MCLs are enforceable standards that regulate the
concentration of specific organic and inorganic contaminants
that have been determined to adversely affect human health in
public drinking water supplies. MCLs are relevant and
appropriate for the groundwater at the Site because the
aquifer is a potential source of drinking water.
MCLs were used in determining groundwater preliminary
remediation goals (PRGs) for site contaminants where such
contaminant levels have been established. Under the DGGW-
2 component of the selected remedy, MNA (with a
contingency for active groundwater treatment) will over time
result in the groundwater in the DGGW achieving PRGs.
EPA Risk Reference Doses (RfDs)
To be considered
RfDs are dose levels developed by EPA for use in estimating
the non-carcinogenic risk resulting from exposure to toxic
substances.
RfDs were used to assess health risks due to exposure to non-
carcinogenic chemicals in groundwater, and to develop of
acceptable groundwater PRG concentrations. Under the
DGGW-2 component of the selected remedy, MNA (with a
contingency for active groundwater treatment) will over time
result in the groundwater in the DGGW achieving PRGs.
EPA Human Health Assessment Cancer
Slope Factors (CSFs)
To be considered
CSFs are developed by EPA for health effects assessments or
evaluation by the Human Health Assessment Group. These
values present the most up-to-date cancer risk potency
information and are used to compute the individual
incremental cancer risk resulting from exposure to
carcinogens.
CSFs were used to compute the individual cancer risk
resulting from exposure to contaminants in groundwater, and
in the development of acceptable groundwater PRG
concentrations. Under the DGGW-2 component of the
selected remedy, MNA (with a contingency for active
groundwater treatment) will over time result in the
Broundwater in the DGGW achieving PRGs.
Groundwater
Guidelines for Carcinogen Risk
Assessment (EPA/630/P-03/001F,
March 2005)
To be considered
Guidance values were used"to evaluate the potential
carcinogenic hazard caused by exposure to contaminants.
Cancer risks identified will be addressed by the DGGW-2
component of the selected remedy.
Supplemental Guidance for Assessing
Susceptibility from Early-Life Exposure
to Carcinogens (EPA/B30/R-03/003F,
March 2005)
To be considered
Guidance values were used to evaluate the potential
carcinogenic hazard to children caused by exposure to
contaminants.
Child cancer risks identified will be addressed by the DGGW-2
component of the selected remedy.
EPA Office of Water, Drinking Water
Health Advisories EPA 822-R-06-013
To be considered
Health Advisories (HAs) are estimates of acceptable drinking
water levels for chemical substances based on health affects
information; an HA is not a legally enforceable Federal
standard, but serves as technical guidance to assist federal,
state and local officials. HAs were used if constituents did not
have promulgated MCLs.
HAs were used to develop acceptable groundwater PRG
concentrations. Under the DGGW-2 component of the
selected remedy, MNA (with a contingency for active
groundwater treatment) wil! over time result in the
groundwater in the DGGW achieving PRGs.
State Regulatory Requirements
Massachusetts Groundwater Quality
Standards (314 CMR 6.00)
Applicable
These standards consist of ground water classifications, which
designate and assign the uses for which the various ground
waters of the Commonwealth shall be maintained and
protected; water quality criteria necessary to sustain the
designated uses; and regulations necessary to achieve the
designated uses or maintain the existing ground water quality.
The GWQSs set numeric limits for certain contaminants' as
well as a pH range. They were used when they were more
strinflent than Federal MCLs.
Groundwater beneath the Site is mapped in a potentially
productive aquifer with the potential for potable water use.
Under the DGGW-2 component of the selected remedy, MNA
(with a contingency for active groundwater treatment) will over
time result In the groundwater in the DGGW achieving PRGs.
Sutton Brook Disposal Area SF Site
TewKsbufy, Massachusetts
Page 1 of 2
Record of Decision
September 2007
-------
TABLE M-10
ALTERNATIVE DGGW-2
CHEMICAL SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
Groundwater
(Cont'd)
Massachusetts Drinking Water
Standards (310 CMR 22.00)
Relevant and appropriate
These standards establish Massachusetts MCLs for organic
and inorganic contaminants that have been determined to
adversely affect human health in public drinking water
systems. The aquifer on-site is not a public water system, but
these requirements are R&A because the aquifer has the
potential to be used as a source of drinking water. These
requirements were used when they were mare stringent than
Federal MCLs.
Under the DGGW-2 component of the selected remedy, MNA
(with a contingency for active groundwater treatment) will over
time result in the groundwater in the DGGW achieving PRGs.
Massachusetts DEP Office of Research
and Standards Guidelines (ORSGs)
To be considered
The Massachusets DEP Office of Research and Standards
issues guidance for chemicals other than those with
Massachusetts MCLs in drinking water. ORSGs are
concentration of chemicals in drinking water, at or below
which, adverse health effects are unlikely to occur after
chronic (lifetime) exposure. These guidance values were used
when constituents did not have promulgated MCLs.
Under the DGGW-2 component of the selected remedy, MNA
(with a contingency for active groundwater treatment) will over
time result in the groundwater in the DGGW achieving PRGs.
Sutton Brook Otspc&ai Area SF Site
Tewksbury, Massachusetts
Page 2 of 2
Record of Decision
September 2007
-------
TABLE M-11
ALTERNATIVE DGGW-2
ACTION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
#iAAriladl»-iw-- ,}¦
-W ¦¦
Federal ReqHistory Requirements
RCRA Subtitle C - Hazardous Waste
Identification and Listing Regulations (40 CFR
Parts 260-262 and 40 CFR 264,13)
Applicable
Massachusetts has been delegated the authority to administer
these RCRA standards through its state hazardous waste
management regulations. These provisions have been adopted by
the State, These regulations include rules to identify hazardous
waste and a requirement to obtain a detailed chemical and
physical analysis of a representative sample of any hazardous
wastes prior to treatment, storage, or disposal.
Because RCRA-type (listed or characteristic) hazardous
wastes were disposed of at the Site during the operation of the
landfill, this requirement was determined to be applicable. Any
media generated as part of monitoring activities and
groundwater extraction and treatment will be tested for
hazardous waste characteristics. If determined to be
hazardous waste, then they will be stored, transported, or
disposed of in accordance with 40 CFR Part 264.
RCRA 40 CFR 264 Subpart 1, Use and
Management of Containers
Applicable if containers
are used in the remedial
action
Massachusetts has been delegated the authority to administer
these RCRA standards through its state hazardous waste
management regulations. These provisions have been adopted by
the State. This regulation establishes requirements for the storage
of containers of hazardous waste.
Because RCRA-type (listed or characteristic) hazardous
wastes were disposed of at the Sits during the operation of the
landfill, if the active groundwater treatment contingency is
needed for the DGGW-2 component of the selected remedy
and if a container is used to store hazardous waste, then
DGGW-2 will be implemented to comply with this ARAR.
Waste
RCRA 40 CFR 264 Subpart J, Tank Systems
Applicable if tank systems
are used in the remedial
action
Massachusetts has been delegated the authority to administer
these RCRA standards through its state hazardous waste
management regulations. These provisions have been adopted by
the State. This regulation establishes requirements for the use of
tank systems for storing or treating hazardous waste.
Because RCRA-type (listed or characteristic} hazardous
wastes were disposed of at the Site during the operation of the
landfill, if the active groundwater treatment contingency is
needed for the DGGW-2 component of the selected remedy
and if a tank system is used to store hazardous waste, then
DGGW-2 will be implemented to comply with this ARAR.
RCRA40 CFR 264 Subpart X, Miscellaneous
Units
Applicable if
miscellaneous units are
used in the remedial
action
Massachusetts has been delegated the authority to administer
these RCRA standards through its state hazardous waste
management regulations. These provisions have been adopted by
the State. This regulation establishes requirements for the use of
miscellaneous units for treating, storing, or disposing of hazardous
waste.
Because RCRA-type (listed or characteristic} hazardous
wastes were disposed of at the Site during the operation of the
landfill, if the active groundwater treatment contingency is
needed for the DGGW-2 component of the selected remedy
and if a miscellaneous unit is used to store hazardous waste,
then DGGW-2 will be implemented to comply with this ARAR.
RCRA 40 CFR 264 Subpart AA, Air Emission
Standards for Process Vents
Applicable if thresholds
are met
This regulation establishes air emission standards for process
vents, closed-vent systems, and control devices at hazardous
waste facilities.
If the active groundwater treatment contingency is needed for
the DGGW-2 component of the selected remedy, if a process
vent is used in the remedial action and if applicable thresholds
are met, then air emission controls will be implemented during
groundwater treatment to comply with this regulation.
RCRA 40 CFR 264 Subpart B0. Air Emission
Standards for Equipment Leaks
Applicable if thresholds
are met
This regulation contains air pollutant emission standards for
equipment leaks at hazardous waste TSD facilities. This subpart
applies to equipment that contains or contacts hazardous wastes
with organic concentrations of at least 10 percent by weight.
If the active groundwater treatment contingency is needed for
the DGGW-2 component of the selected remedy and if
equipment covered by this standard is used in the remedial
action and handles hazardous wastes at concentrations that
meet this rule's threshold, then a leak detection and repair
program will be implemented during groundwater treatment to
comply with this regulation.
Sutton Brook Disposal Area SF Site
Tewksbury, Massachusetts
Page 1 of 4
Record of Decision
September 2007
-------
TABLE M-11
ALTERNATIVE DGGW-2
ACTION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
riMRMNSMabavSMNIMi
^^SJSlliSSs)*feiS^.rSumii»aJVofReoulwment •: ¦ ~i\
Waste (cont'd)
RCRA 40 CFR 284 Subpart CC, Air Emission
Standards for Tanks, Surface Impoundments
and Containers
Applicable if thresholds
are met
This regulation establishes air emission standards for facilities that
treat, store, or dispose hazardous wastes in tanks, surface
impoundments, or containers.
Any media generated as part of monitoring activities and
groundwater treatment (if the contingency is needed) will be
tested for hazardous waste characteristics. If determined to
be hazardous waste, then they will be stored, transported, or
disposed of in accordance with 40 CFR Part 264. If a tank or
container is used In the remedial action and if applicable
thresholds are met, then air emission controls will be
implemented during groundwater treatment to comply with this
regulation.
RCRA 40 CFR 264 Subpart DD, Containment
Buildings
Applicable
This regulation contains design, operating, closure and post-
closure standards and requirements for the storage and treatment
of hazardous waste in containment buildings.
If the active groundwater treatment contingency is needed for
the DGGW-2 component of the selected remedy and if a
building is used to house treatment equipment, then the
design, operation, closure, and post-closure of the treatment
building for DGGW-2 will comply with this regulation.
Federal Regulatory Rsquire merits
Clean Water Act Section 402 National
Pollutant Discharge Elimination System
(NPDES) (40 CFR Part 122-125 and 131)
Applicable
This act and regulations establish discharge limitations, monitoring
requirements, and best management practices. Point-source
discharges of effluent to surface water must comply with NPDES
requirements (e.g., federal arid state ambient water quality criteria
(AWQC)).
If the active groundwater treatment contingency is needed for
the DGGW-2 component of the selected remedy, on-site
discharges to surface waters, including Sutton Brook and
adjacent wetlands, shall meet these substantive discharge
standards. These discharge limitations shall also be used to
develop monitoring standards for surface waters.
Surface Water
Clean Water Act (CWA) Ambient Water Quality
Criteria(AWQC) (33 use 1251 Btseq.) (40
CFR 122.44)
Relevant and appropriate
Federal AWQC are recommended (non-enforceable) criteria
published by EPA and provided to the States. AWQC are listed for
protection of ecological and human health for approximately 160
contaminants. AWQC are used in establishing State water quality
standards.
If the active groundwater treatment contingency is needed for
the DGGW-2 component of the selected remedy and if treated
groundwater is discharged to surface water, it will be treated
as needed to comply with State water quality standards based
on AWQC. Surface water monitoring will be performed.
These standards will be used to help assess the effectiveness
of the groundwater treatment.
Clean Water Act (CWA) Pretreatment
Regulations for Discharges to a ROTW (40
CFR Part 403
Applicable if treated
groundwater is discharged
to the POTW
These regulations prohibit the introduction of pollutants into a
publicly owned treatment works (POTW) and has pretreatment
requirements for sources to a POTW
If the active groundwater treatment contingency is needed for
the DGGW-2 component of the selected remedy and if treated
groundwater is discharged to the local POTW, it will be treated
as need to comply with these pretreatment requirements.
State Regulatory Requirements
Mass. Clean Waters Act - MassDEP Surface
Water Discharge Permit Program (314 CMR
3.00; MGL c. 21 Sections 26-63)
Applicable
This act and program establish the requirements intended to
maintain the quality of surface waters by controlling the direct
discharge of pollutants to surface waters. Direct discharge of
wastewater to surface waters must meet effluent discharge limits
established by this program.
If the active groundwater treatment contingency is needed for
the DGGW-2 component of the selected remedy, on-site
discharges to surface waters, including Sutton Brook and
adjacent wetlands, shall meet these substantive discharge
standards. These discharge limitations shall also be used to
develop monitoring standards for surface waters.
Sutton Brook Disposal Area SF Site
Tewksbuty, Massachusetts
Page 2 of 4
Record of Decision
September 2007
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TABLE M-11
ALTERNATIVE DGGW-2
ACTION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
Surface Water
(Cont'd)
Massachusetts Surface Water Quality
Standards (314 CMR 4.00)
Applicable
The Massachusetts Surface Water Quality Standards designate
tie most sensitive uses tor which the various waters of the
Commonwealth shall be enhanced, maintained and protected;
which prescribe the minimum water quality criteria required to
sustain the designated uses; and which contain regulations
necessary to achieve the designated uses and maintain existing
water quality including, where appropriate, the prohibition of
discharges. These regulations limit or prohibit discharges of
pollutants to surface waters to ensure lhat the surface water quality
standards of the receiving waters are protected and maintained or
attained.
If the active groundwater treatment contingency is needed for
the DGGW-2 component of the selected remedy, on-site
discharges to surface waters, including Sutton Brook and
adjacent wetlands, shall meet these substantive discharge
standards. These discharge limitations shall also be used to
develop monitoring standards for surface waters.
MassDEP Surface Water Discharge Permit
Program (314 CMR 3.00)
Applicable
These regulations are intended to protect surface water bodies in
the Commonwealth by regulating the discharge into them. Dined
discharges of wastewater to surface waters must meet effluent
discharge limits established by this program.
If the active groundwater treatment contingency is needed for
the DGGW-2 component of the selected remedy, on-site
discharges to surface waters, including Sutton Brook and
adjacent wetlands, shall meet these substantive discharge
standards. These discharge limitations shall also be used to
develop monitoring standards for surface waters.
Massachusetts Pretreatment Standards for
Discharges to Wastewater Treatment Worfcs
(314 CMR 12.00)
Applicable
These regulations prohibit the introduction of pollutants into a
publicly owned treatment works (POTW) and has pretreatment
requirements for sources to a POTW
If the active groundwater treatment contingency is needed for
the DGGW-2 component of the selected remedy and if treated
groundwater is discharged to the local POTW, it will be treated
as need to comply with these pretreatment requirements.
Federal Regulatory Requirements
RCRA Subtitle C - Releases from Solid Waste
Management Units (40 CFR Subpart F,
264.95 and 234.96(a) and (c))
Applicable
These regulations identify specific monitoring requirements
applicable to hazardous waste facilities, including specifying the
point of compliance at which the groundwater protection standards
apply and at which monitoring must be conducted, as well as
specifying the compliance period during which the groundwater
protection standard applies.
The DGGW-2 component of the selected remedy will be
implemented to comply with these requirements. Because
EPA has determined that the point of compliance at which the
groundwater protection standards apply is the edge of the
waste management unit (the landfill lobes), these standards
will be met throughout the DGGW area.
Groundwater
Underground Injection (40 CFR Part 144)
Relevant arid appropriate
These regulations provide regulatory compliance standards for
treatment facilities that inject wastes underground. The use at
wells to dispose of hazardous waste is prohibited.
If the active groundwater treatment contingency is needed for
the DGGW-2 component of the selected remedy and if the
performance of the DGGW-2 component of the selected
remedy utilizes underground injection for the treated
groundwater or uses an infiltration gallery or any other system
that disposes of treatment water or waste into groundwater as
the remediation technology, groundwater will be treated to be
rion-hazardous prior to subsurface discharge.
Final OSWER Directive "Use of Monitored
Natural Attenuation at Superfund, RCRA
Corrective Action, and Underground Storage
Tank Sites (OSWER Dir. 9200.4-17P, 4/12/99)
To be considered
This guidance sets criteria for evaluating monitored natural
attenuation as a remedy at, among others, Superfund sites.
For the DGGW-2 component of the selected remedy,
monitored natural attenuation was determined to be
appropriate in accordance with this TBC Under DGGW-2,
contaminant levels in the groundwater plume underneath the
DGGW area will be monitored consistent with this guidance.
Active groundwater treatment is retained as a contingency if
determined to be necessary as described in Part 2 of the
ROD.
Sutton Brook Disposal Area SF Site
Massad-uj setts
Page 3 of 4
Record of Decision
September 2007
-------
TABLE M-11
ALTERNATIVE DGGW-2
ACTION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
State Regulatory Requirements
Groundwater
MassOEP Underground Injection Control
Regulations (310 CMR 27.00)
Applicable
These regulations are intended to protect underground sources of
drinking water by regulating the underground injection of
hazardous wastes, fluids used for extraction of minerals, oil, and
energy, and any other fluids having potential to contaminate
groundwater.
If the active groundwater treatment contingency Is needed for
the DGGW-2 component of the selected remedy and if the
performance of the DGGW-2 component of the selected
remedy utilizes underground injection tor the treated
groundwater or uses an infiltration gallery or any other system
that disposes of treatment water or waste into groundwater as
the remediation technology, groundwater will be treated to be
non-hazardous prior to subsurface discharge.
(Cont'd}
MassDEP Groundwater Discharge Permit
Program (314 CMR 5,00)
Applicable
These regulations are intended to protect groundwater quality by
controlling the discharge of pollutants to the ground waters of the
Commonwealth to assure that these waters are protected for their
highest potential use. These regulations set effluent limits for the
discharge of pollutants to groundwater.
If the active groundwater treatment contingency is needed for
the DGGW-2 component of the selected remedy and if this
contingent remedy utilizes underground injection, infiltration
gallery or any other system that disposes of treatment water or
waste into groundwater as the remediation technology,
groundwater will be treated to meet the substantive
requirements of these regulations prior to subsurface
discharge.
Massachusetts Well Decommissioning
Requirements (313 CMR 3.03)
Applicable
These regulations provide for certain notification requirements
upon well abandonment.
These regulations will be followed to the extent that the
alternative involves decommissioning any wells.
Federal Regulatory Requirements
Clean Air Act National Emissions Standards foe
Hazardous Air Pollutants (NESHAPs), 40 CFR
Part 61
Applicable
These regulations set standards for emissions of 189 Hazardous
Air Pollutants that are listed in Section 112(b)(1) of the Clean Air
Act.
If the active groundwater treatment contingency is needed for
the DGGW-2 component of the selected remedy and if air •
stripping is used and any of the 189 hazardous air pollutants
are emitted, then DGGW-2 will comply with this ARAR.
OSWER Directive 9355.0-28. Air Stripper
Control Guidance, 7/12/89
To be considered
This OSWER directive establishes guidance on the control of air
emissions from air strippers used at Superfund sites for
groundwater treatment.
If the active groundwater treatment contingency is needed tor
the DGGW-2 component of the selected remedy and if air
stripping is used, then DGGW-2 will comply with this policy.
State Regulatory Requirements
Air
Massachusetts Ambient Air Quality Standards
(310 CMR 6.00)
Applicable
These regulations set primary and secondary standards for
emissions of sulfur oxides, particulate matter, carbon monoxide,
ozone, nitrogen dioxide, and lead.
If the active groundwater treatment contingency is needed for
the DGGW-2 component of the selected remedy and if air
stripping Is used, then DGGW-2 will comply with this policy.
No air emissions from remedial treatment will cause ambient
air quality standards to be exceeded.
MassDEP Revised Ambient Air Guidelines
(December 6,1995)
To be considered
This document presents MassDEP's revised ambient air
guidelines, presenting the Threshold Effects Exposure Limits
(TELs) and Allowable Ambient Limits (AALs).
The DGGW-2 component of the selected remedy will be
designed and implemented to comply with this policy.
Massachusetts Air Pollution Control
Regulations (310 CMR 7.00)
Applicable
This regulation stipulates that during construction and/or demolition
activities, air emissions (i.e. dust, particulates, etc.) must be
controlled to prevent air pollution.
Construction activities will be managed to meet the standards
for visible emissions (310 CMR 7.06); dust, odor, construction,
and demolition (310 CMR 7.09); and noise (310 CMR 7.10). If
the active groundwater treatment contingency is needed for
the DGGW-2 component of the selected remedy and if air
stripping is used, then DGGW-2 will comply with this ARAR.
Odor emissions from the groundwater treatment air stripper
will be controlled with best available control technology.
Sutton Brook Disposal Area SF Site
Tewksftury, Massachusetts
Page 4 of A
Record of Decision
SeptemUer 200?
-------
TABLE M-12
ALTERNATIVE DGGW-2
LOCATION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
Federal Regulatory Requirements and Guidance
Wetlands Executive Older
(E011990), 40 CFR 6.302(a),
and 40 CFR Part 6, Appendix
A
Applicable
The Wetlands Executive Order requires federal agencies to avoid
undertaking or providing assistance for new construction located in
wetlands unless there is no practicable alternative and the proposed
action includes all practicable measures to minimize the destruction,
toss, or degradation of wetlands, and preserve and enhance natural
and beneficial values of wetlands.
If the active groundwater treatment contingency for the DGGW-2
component of the selected remedy is needed, the installation of
welts and possible treatment plant may unavoidably impact
wetlands. During remedial design, the effects of remedial activities
on the wetlands will be evaluated and minimized. Compensatory
wetlands mitigation will be performed as necessary to comply with
this ARAR for those unavoidable minimal Impacts.
Surface Water,
Clean Water Act Section 404
Dredge arid Fill Regulations
(40 CFR 230,33 CFR 320-
323)
Applicable
These regulations outline the requirements for the discharge of
dredged or fill materials into surface waters including wetlands. No
activity that impacts waters of the United States shall be permitted if
a practicable alternative that has less adverse impact exists, If
there Is no other practicable alternative, the impacts must be
mitigated.
If the active groundwater treatment contingency for the DGGW-2
component of the selected remedy is needed, the installation of
wells and possible treatment plant may unavoidably impact
wetlands. During remedial design, the effects of remedial activities
on the wetlands will be evaluated and avoided and/or minimized.
Compensatory wetlands mitigation will be performed as necessary
to comply with this ARAR for those unavoidable minimal impacts.
Alternative DGGW-2 is the least environmentally damaging
practicable alternative that meets the remedial action objectives.
Wetlands,
Floodplains
Floodplains Executive Order
(EO11988), 40 CFR 6.302(b),
and 40 CFR Part 6, Appendix
A
Applicable
The Floodplains Executive Order requites federal agencies to avoid
impacts associated with the occupancy and modification of a
floodplain unless there is no practicable alternative and the
proposed action includes all practicable measure to reduce the risk
of flood loss, to minimize the impact of floods, and to restore and
preserve the natural and beneficial values of floodplains.
Under the DGGW-2 component of the setected remedy, available
practicable means will be used to reduce the risk of flood loss, to
minimize the impact of floods, and to restore and preserve the
floodplains. In areas where the landfill cover will result in the fling in
of areas within the 100-yearfIoodplain, there will be a replication of
100-year floodplain space equivalent to the amount loss by the final
cover. Stormwater management basins will be designed to
minimize the impact of floods.
RCRA Floodplain Restrictions
tor Hazardous Waste Faeitties
(40 CFR 264.18(b))
Relevant and Appropriate
These regulations require that a hazardous waste facility located in
a 100-year floodplain must be designed, constructed, operated, and
maintained to prevent washout by a 100-year storm.
Under the DGGW-2 component of the selected remedy, hazardous
waste facility. Including the the contingent remedy's possible
treatment plant, will be designed, constructed, operated, and
maintained with all available practicable means to reduce the risk of
Hood loss, to minimize the impact of floods, and to restore and
preserve the floodplains. In areas where the treatment plant will
result in the filling in of areas within the »00-year floodplain, there will
be a replication of 100-year floodplain space equivalent to the
amount loss. Stormwater management basins will be designed to
minimize the impact of floods. Any structures will be designed to
withstand the effects of a 100-year storm.
Sutton Brook Disposal Area SF Sfte
Tewksbury, Massachusetts
Page 1 of 3
Record of Decision
September 20Q?
-------
TABLE M-12
ALTERNATIVE DGGW-2
LOCATION SPECIFIC ARARs and TBCs
Suttori Brook Disposal Area Superfund Site, Tewksbury. Massachusetts
State Regulatory Requirements
Massachusetts Wetlands
Regulations (310 CMR 10.00;
MGLc. 131, Section 40:
Wetlands Protection Act)
Applicable
These regulations set performance standards for dredging, filling,
and altering of any inland wetland, the buffer zona within 100 feet of
a wetland, and the riverfront area (defined as the area between the
rivet's mean annual high-water line and a line located 200 feet
away). The requirement also defines wetlands based on vegetation
type and requires that effects on wetlands be mitigated. Resource
areas at the Site cowered by the regulations include banks,
bordering vegetated wetlands, land under bodies of water, land
subject to flooding, riverfront and estimated habitats of rare wildlife.
Under this requirement, available alternatives must be considered
that minimize the extent of adverse impacts, and mitigation including
restoration and/or replication is required.
Under the DGGW-2 component of the selected remedy, the
installation of wells and possible treatment plant (if the active
groundwater treatment contingency is needed) will occur within the
100 foot buffer zone of wetlands and the riverfront area. If the
active groundwater treatment contingency is needed, wetlands and
the riverfront area may be unavoidably impacted. All practicable
means will be used to avoid or minimize harm to the wetland buffer
zone and the riverfront area, including erosion and sedimentation
controls and stormwater management. The wetland buffer zone
area and riverfront area unavoidably disturbed by remedial activities
will be mitigated, restored or preserved.
Surface Water,
Wetlands,
Floodpiains
(Cont'd)
Massachusetts Water Quality
Certification for Discharge of
Dredged or Fill Material,
Dredging, and Dredging
Material Disposal in Waters of
the U.S. within the
Commonwealth (314 CMR
9.00)
Applicable
For discharges of dredged or fill material: there must be no
practicable alternative with less adverse impact on the aquatic
ecosystem: appropriate and practicable steps must be taken to
avoid and minimize potential adverse impacts to wetlands and land
underwater; stormwater discharges must be controlled with BMPs;
and there must not be substantial adverse impacts to the physical,
chemical, or biological integrity of surface waters. For dredging and
dredged material management there must be no practicable
alternative with less adverse impact on the aquatic ecosystem; and
if avoidance is not passible then minimize, or if neither avoidance or
minimization are possible, then mitigate potential adverse impacts.
Under the DGGW-2 component of the selected remedy, the
installation of wells and possible treatment plant (if the active
groundwater treatment contingency is needed) will occur within the
100 foot buffer zone of wetlands and the riverfront area. If the
active groundwater treatment contingency is needed, wetlands and
the riverfront area may be unavoidably impacted. All practicable
means wilt be used to avoid or minimize harm to the wetland buffer
zone and the riverfront area, including erosion and sedimentation
controls and stormwater management. The wetland buffer zone
area and riverfront area unavoidably disturbed by remedial activities
will be mitigated, restored or preserved. There would be no
substantial long-term adverse impacts to the integrity of surfaea
waters.
Massachusetts Waterways
Regulations (310 CMR 9.00)
Applicable
These regulations set forth criteria for work within flowed and filled
tideiands and other waterways. Waterways concerns focus on the
long term viability of marine uses and protecting public rights in
tideiands, including fishing and access.
If the active groundwater treatment contingency for the DGGW-2
component of the selected remedy is needed, the installation of
wells and possible treatment plant may unavoidably impact
wetlands. During remedial design, the effects of remedial activities
on the wetlands will be evaluated and avoided and/or minimized.
Compensatory wetlands mitigation will be performed as necessary
to comply with this ARAR for those unavoidable minimal impacts.
Massachusetts Hazardous
Waste Rules, Facility Location
Standards (310 CMR 30.700)
Applicable
These regulations set forth criteria for siting hazardous waste
facilities within Land Subject to Flooding (as defined under the
Massachusetts Wetlands Protection standards); surface water
supplies; and actual, planned, or potential public water supplies
Under the DGGW-2 component of the selected remedy, any
hazardous waste facility, including the the contingent remedy's
possible treatment ptant, within Land Subject to Flooding and
potential public water supply area, will be designed, constructed,
operated, and maintained to prevent a release of hazardous waste
within the protected resource area.
Sutton Brook Disposal Area SF Site
Tewksbury, Massachusetts
Page 2 of 3
Record of Decision
September 2007
-------
TABLE M-12
ALTERNATIVE DGGW-2
LOCATION SPECIFIC ARARs and TBCs
Sutton Brook Disposal Area Superfund Site, Tewksbury, Massachusetts
:i . vi JI^ulran^iSaXee^ia^'.JifStMtu. SummarvofR®ouIren>ent .. .:.vl
Federal Regulatory Requirements
Endangered Species Act (16
USC 1531 et sec.: 40 CFR
6.302(h); 50 CFR 402)
Applicable if encountered
This statute requires that Federal agencies avoid activities which
jeopardize threatened or endangered species or adversely modify
habitats essential to their survival. Mitigation measures should be
considered * a listed species or habitat may be jeopardized.
No endangered or threatened species have been identified at the
Site to date. If endangered or threatened species in the site area
are identified, remedial activities would avoid actions that would
adversely affect threatened or endangered species or habitats.
National Historic Preservation
Act (16 USC 470 et seq., 36
CFR BOO)
Applicable if encountered
Pursuant to Sections 106 and 110(f) of the NHPA, as amended.
CERCLA response actions are required to take into account the
effects of the response activities on any historic property included or
eligible for inclusion on the National Register of Historic Places.
Should the DGGW-2 component of the selected remedy impact
historic properties, as determined in the remedial design, activities
will be coordinated with the Massachusetts Historical Commission
(MHC), If it is determined that adverse impacts are unavoidable,
then MHC will be consulted to determine ways to minimize andfor
mitigate such adverse impacts.
State Regulatory Requirements
Other Natural
Resources
Antiquities Act and
Regulations; Massachusetts
Historical Commission;
Protection or Properties
included in the State Register
of Historic Places (M.G.L. ch. 9,
sec. 26-27; 950 CMR 70.00)
Appfcable if encountered
These regulations require the adoption of all prudent and feasible
means to eliminate, minimize or mitigate adverse effects to historic
or archaeological properties, and require coordination with the
Massachusetts Historical Commission.
Should the DGGW-2 component of the selected remedy impact
historic or archaeological properties, as determined in the remedial
design, activities will be coordinated with the Massachusetts
Historical Commission (MHC). If it is determined that adverse
impacts cannot be eliminated, then MHC will be consulted to
determine ways to minimize and/or mitigate such adverse impacts.
Massachusetts Endangered
Species Act, 321 CMR 10.00,
(MGL c. 131A)
Applcable if encountered
The Commonwealth of Massachusetts has the authority to
research, list, and protect any species deemed endangered,
threatened, or of other special concern. These species are listed as
either endangered, threatened, or species of special concern in the
regulations. Actions must be conducted in a manner that minimizes
the effect on Massachusetts-listed endangered species and species
listed by the Massachusetts Natural Heritage Program.
No endangered or threatened species have bean identified at the
Site to date. If endangered or threatened species in the site area
are identified, remedial activities would avoid actions that would
adversely affect threatened or endangered species or habitats.
Sutton Brook Disposal Area SF Site
Tewksfauty, Massachusetts
Page 3 of 3
Record of Decision
September 2007
-------
Appendix E
Administrative Record Index and Guidance Documents
-------
Sutton Brook
NPL Site Administrative Record File
Record of Decision (ROD)
Operable Unit 1 - Sitewide
Index
ROD Dated September 2007
Released October 2007
Prepared by
EPA New England
Office of Site Remediation & Restoration
-------
Introduction to the Collection
This is the administrative record for the Sutton Brook Superfund Site, Tewksbury, MA, Operable
Unit 1, Record of Decision (ROD), released September, 2007. The file contains site-specific
documents and a list of guidance documents used by EPA staff in selecting a response action at
the site.
This administrative record should replace the Proposed Plan for Record of Decision
administrative record file dated June 2007. This file includes, by reference, the administrative
record file for the Sutton Brook Removal Action, issued July 20, 2000.
The administrative record file is available for review at:
EPA New England Office of
Site Remediation & Restoration
(OSRR) Records and Information Center
1 Congress Street, Suite 1100 (HSC)
Boston, MA 02114
(by appointment)
617-918-1440 (phone)
617-918-1223 (fax)
www.epa.gov/region01/superfund/resource/records.htm
Questions about this administrative record file should be directed to the EPA New England site
manager.
An administrative record file is required by the Comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA), as amended by the Superfund Amendments and
Reauthorization Act (SARA).
Tewksbury Public Library
300 Chandler Street
Tewksbury, MA 01876
(978) 640-4490 (phone)
http ://www.tewksburypl. org /
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10/1/2007
Page 1 of 24
03: REMEDIAL INVESTIGATION (RI)
273524 GROUNDWATER USE AND VALUE DETERMINATION
Author: US EPA REGION 1
Addressee:
Doc Type: REPORT
273538 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) MAY 2004
(6/14/2004 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
273539 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) JUNE 2004
(7/14/2004 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
273540 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) JULY 2004
(8/13/2004 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN Doc Date: 07/01/2004 # of Pages: 3
Addressee: DON MCELROY US EPA REGION 1 File Break: 03.06
Doc Type: REPORT
AR Collection: 11866
ROD Admin. Record
AR Collection QA Report
***For External Use***
Doc Date: 07/01/2001 # of Pages: 5
File Break: 03 .06
Doc Date: 05/01/2004 # of Pages: 3
File Break: 03 .06
Doc Date: 06/01/2004 # of Pages: 3
File Break: 03 .06
-------
AR Collection: 11866
ROD Admin. Record
AR Collection QA Report
***For External Use***
10/1/2007
Page 2 of 24
03: REMEDIAL INVESTIGATION (RI)
273541 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) AUGUST 2004
(9/14/2004 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
Doc Date: 08/01/2004
File Break: 03 .06
# of Pages: 4
273542 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) SEPTEMBER
2004 (10/14/2004 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
Doc Date: 09/01/2004
File Break: 03 .06
# of Pages: 5
273543 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) OCTOBER
2004 (11/14/2004 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
Doc Date: 10/01/2004
File Break: 03 .06
# of Pages: 4
273544 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) NOVEMBER
2004 (12/14/2004 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN
Addressee:
DON MCELROY US EPA REGION 1
Doc Date: 11/01/2004
File Break: 03 .06
# of Pages: 5
Doc Type: REPORT
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10/1/2007
Page 3 of 24
03: REMEDIAL INVESTIGATION (RI)
273520 REQUEST FOR ADDITIONAL MONITORING LOCATION
Author: KARL D KASPER WOODARD & CURRAN INC
Addressee: DON MCELROY US EPA REGION 1
Doc Type: LETTER
273546 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) DECEMBER
2004 (1/14/2005 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
273545 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) JANUARY
2005 (2/14/2005 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
273547 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) FEBRUARY
2005 (3/11/2005 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN Doc Date: 02/01/2005 # of Pages: 3
Addressee: DON MCELROY US EPA REGION 1 File Break: 03.06
Doc Type: REPORT
AR Collection: 11866
ROD Admin. Record
AR Collection QA Report
***For External Use***
Doc Date: 11/19/2004 # of Pages: 2
File Break: 03 .02
Doc Date: 12/01/2004 # of Pages: 4
File Break: 03 .06
Doc Date: 01/01/2005 # of Pages: 3
File Break: 03 .06
-------
AR Collection: 11866
ROD Admin. Record
AR Collection QA Report
***For External Use***
10/1/2007
Page 4 of 24
03: REMEDIAL INVESTIGATION (RI)
273548 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) MARCH 2005
(4/14/2005 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
Doc Date: 03/01/2005
File Break: 03 .06
# of Pages: 3
273526 REVIEW OF DRAFT REMEDIAL INVESTIGATION AND FEASIBILITY STUDY (RI/FS) PHASE 1A REMEDIAL
INVESTIGATION (RI) DELIVERABLE, MASTER COMMENT LIST
Author: US EPA REGION 1
Addressee:
Doc Date: 03/04/2005
File Break: 03 .06
# of Pages: 24
Doc Type: MEMO
273549 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) APRIL 2005
(5/13/2005 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
Doc Date: 04/01/2005
File Break: 03 .06
# of Pages: 3
273550 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) MAY 2005
(6/13/2005 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN
Addressee:
DON MCELROY US EPA REGION 1
Doc Type: REPORT
Doc Date: 05/01/2005 # of Pages: 11
File Break: 03 .06
-------
AR Collection: 11866
ROD Admin. Record
AR Collection QA Report
***For External Use***
10/1/2007
Page 5 of 24
03: REMEDIAL INVESTIGATION (RI)
273551 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) JUNE 2005
(7/14/2005 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
Doc Date: 06/01/2005
File Break: 03 .06
# of Pages: 3
273552 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) JULY 2005
(8/12/2005 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
Doc Date: 07/01/2005 # of Pages: 3
File Break: 03 .06
273553 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) AUGUST 2005
(9/14/2005 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
Doc Date: 08/01/2005
File Break: 03 .06
# of Pages: 3
273554 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) SEPTEMBER
2005 (10/14/2005 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN
Addressee:
DON MCELROY US EPA REGION 1
Doc Date: 09/01/2005
File Break: 03 .06
# of Pages: 4
Doc Type: REPORT
-------
AR Collection: 11866
ROD Admin. Record
AR Collection QA Report
***For External Use***
10/1/2007
Page 6 of 24
03: REMEDIAL INVESTIGATION (RI)
273527 REVIEW BY EPA OF RESPONSE TO COMMENTS ON THE MARCH 2005 DRAFT PHASE 1A REMEDIAL
INVESTIGATION (RI) DELIVERABLE
Author: US EPA REGION 1
Addressee:
Doc Type: MEMO
Doc Date: 09/22/2005 # of Pages: 9
File Break: 03 .06
273528 COMMENTS ON THE "RESPONSE TO COMMENTS ON THE MARCH 2005 DRAFT PHASE 1A REMEDIAL
INVESTIGATION (RI) DELIVERABLE"
Author:
Addressee:
US EPA REGION 1
Doc Type: LETTER
Doc Date: 09/22/2005 # of Pages: 3
File Break: 03 .06
273555 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) OCTOBER
2005 (11/14/2005 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
Doc Date: 10/01/2005
File Break: 03 .06
# of Pages: 3
273556 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) NOVEMBER
2005 (12/14/2005 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN
Addressee:
DON MCELROY US EPA REGION 1
Doc Type: REPORT
Doc Date: 11/01/2005
File Break: 03 .06
# of Pages: 4
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AR Collection: 11866
ROD Admin. Record
AR Collection QA Report
***For External Use***
10/1/2007
Page 7 of 24
03: REMEDIAL INVESTIGATION (RI)
273557 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) DECEMBER
2005 (1/14/2006 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
Doc Date: 12/01/2005
File Break: 03 .06
# of Pages: 3
273558 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) JANUARY
2006 (2/14/2006 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
Doc Date: 01/01/2006
File Break: 03 .06
# of Pages: 3
273559 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) FEBRUARY
2006 (3/14/2006 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
Doc Date: 02/01/2006
File Break: 03 .06
# of Pages: 3
273560 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) MARCH 2006
(4/14/2006 TRANSMITTAL ATTACHED)
Author: KARL D KASPAR WOODARD & CURRAN
Addressee:
DON MCELROY US EPA REGION 1
Doc Date: 03/01/2006
File Break: 03 .06
# of Pages: 3
Doc Type: REPORT
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Page 8 of 24
03: REMEDIAL INVESTIGATION (RI)
273561 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) APRIL 2006
(5/12/2006 TRANSMITTAL ATTACHED)
Author: JEFFREY A HAMEL WOODARD & CURRAN
Addressee: KARLDKASPAR WOODARD & CURRAN
DON MCELROY US EPA REGION 1
Doc Type: REPORT
273562 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) MAY 2006
(6/14/2006 TRANSMITTAL ATTACHED)
Author: JEFFREY A HAMEL WOODARD & CURRAN
Addressee: KARLDKASPAR WOODARD & CURRAN
DON MCELROY US EPA REGION 1
Doc Type: REPORT
273563 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) JUNE 2006
(7/14/2006 TRANSMITTAL ATTACHED)
Author: JEFFREY A HAMEL WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
AR Collection: 11866
ROD Admin. Record
AR Collection QA Report
***For External Use***
Doc Date: 04/01/2006 # of Pages: 3
File Break: 03 .06
Doc Date: 05/01/2006 # of Pages: 3
File Break: 03 .06
Doc Date: 06/01/2006 # of Pages: 3
File Break: 03 .06
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Page 9 of 24
03: REMEDIAL INVESTIGATION (RI)
273564 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) JULY 2006
(8/14/2006 TRANSMITTAL ATTACHED)
Author: JEFFREY A HAMEL WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
273565 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) AUGUST 2006
(9/15/2006 TRANSMITTAL ATTACHED)
Author: JEFFREY A HAMEL WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
273566 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) SEPTEMBER
2006 (10/13/2006 TRANSMITTAL ATTACHED)
Author: JEFFREY A HAMEL WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
273567 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) OCTOBER
2006 (11/14/2006 TRANSMITTAL ATTACHED)
Author: JEFFREY A HAMEL WOODARD & CURRAN Doc Date: 10/01/2006 # of Pages: 3
Addressee: DON MCELROY US EPA REGION 1 File Break: 03.06
AR Collection: 11866
ROD Admin. Record
AR Collection QA Report
***For External Use***
Doc Date: 07/01/2006 # of Pages: 3
File Break: 03 .06
Doc Date: 08/01/2006 # of Pages: 3
File Break: 03 .06
Doc Date: 09/01/2006 # of Pages: 3
File Break: 03 .06
Doc Type: REPORT
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10/1/2007
Page 10 of 24
03: REMEDIAL INVESTIGATION (RI)
273568 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) NOVEMBER
2006 (12/14/2006 TRANSMITTAL ATTACHED)
Author: JEFFREY A HAMEL WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
Doc Date: 11/01/2006
File Break: 03 .06
# of Pages: 3
273569 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) DECEMBER
2006 (1/12/2007 TRANSMITTAL ATTACHED)
Author: JEFFREY A HAMEL WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
Doc Date: 12/01/2006
File Break: 03 .06
# of Pages: 3
273532 TECHNICAL MEMORANDUM, NOVEMBER 2006 SEDIMENT SAMPLE COLLECTION - SOUTHERN
TRIBUTARY
Author: WOODARD & CURRAN
Addressee:
Doc Type: REPORT
Doc Date: 12/05/2006 # of Pages: 23
File Break: 03 .02
273570 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) JANUARY
2007 (2/14/2007 TRANSMITTAL ATTACHED)
Author: JEFFREY A HAMEL WOODARD & CURRAN
Addressee:
DON MCELROY US EPA REGION 1
Doc Date: 01/01/2007
File Break: 03 .06
# of Pages: 19
Doc Type: REPORT
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AR Collection: 11866
ROD Admin. Record
AR Collection QA Report
***For External Use***
03: REMEDIAL INVESTIGATION (RI)
273531 TECHNICAL MEMORANDUM, NOVEMBER 2006 SEDIMENT SAMPLE COLLECTION - DEEP MARSH
Author: WOODARD & CURRAN
Addressee:
Doc Type: REPORT
273530 TOXICITY TEST RESULTS - SOUTHERN TRIBUTARY SEDIMENTS
Author: JEFFREY A HAMEL WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: SAMPLING DATA
273519 SAMPLING DATA FOR 19 BEMIS CIRCLE
Author: PAUL GIDDINGS MA DEPARTMENT OF ENVIRONMENTAL PROTECTION - COMMISSIONER
Addressee:
Doc Type: SAMPLING DATA
273571 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) FEBRUARY
2007 (3/15/2007 TRANSMITTAL ATTACHED)
Author: JEFFREY A HAMEL WOODARD & CURRAN Doc Date: 02/01/2007 # of Pages: 3
Addressee: DON MCELROY US EPA REGION 1 File Break: 03.06
10/1/2007
Page 11 of 24
Doc Date: 01/08/2007 # of Pages: 27
File Break: 03 .02
Doc Date: 01/18/2007 # of Pages: 2
File Break: 03 .02
Doc Date: 01/29/2007 # of Pages: 25
File Break: 02.03
Doc Type: REPORT
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***For External Use***
10/1/2007
Page 12 of 24
03: REMEDIAL INVESTIGATION (RI)
273576 REMEDIAL INVESTIGATION AND FEASIBILTY STUDY (RI/FS), VOLUME 1 OF 5, REMEDIAL
INVESTIGATION (RI) REPORT
Author: WOODARD & CURRAN
Addressee:
Doc Type: REM INVEST/FS STUDY (RI/FS)
REMEDIAL INVESTIGATION (RI)
REPORT
Doc Date: 02/01/2007 # of Pages: 342
File Break: 03 .06
273577 REMEDIAL INVESTIGATION AND FEASIBILTY STUDY (RI/FS), VOLUME 2 OF 5, REMEDIAL
INVESTIGATION (RI) REPORT, APPENDICES
Author: WOODARD & CURRAN
Addressee:
Doc Type: REM INVEST/FS STUDY (RI/FS)
REMEDIAL INVESTIGATION (RI)
REPORT
Doc Date: 02/01/2007 # of Pages: 3244
File Break: 03 .06
273533 COMMENTS ON "TRANSMITTAL OF TOXICITY TEST RESULTS - TRIBUTARY SEDIMENTS"
Author: DON MCELROY US EPA REGION 1
Addressee:
Doc Type: MEMO
Doc Date: 02/06/2007
File Break: 03 .02
# of Pages: 1
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10/1/2007
Page 13 of 24
03: REMEDIAL INVESTIGATION (RI)
273521 COMMENTS FOR TRANSMITTAL TO NATIONAL REMEDY REVIEW BOARD
Author: RICH DOHERTY ENGINEERING & CONSULTING RESOURCES, INC
Addressee: DON MCELROY US EPA REGION 1
Doc Type: LETTER
Doc Date: 03/01/2007 # of Pages: 10
File Break: 03 .06
273529 REVIEW BY EPA OF THE REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) BASELINE RISK
ASSESSMENT (HUMAN HEALTH RISK ASSESSMENT (HHRA) PORTION)
Author: US EPA REGION 1
Addressee:
Doc Type: MEMO
Doc Date: 03/01/2007 # of Pages: 6
File Break: 03.10
273572 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) MARCH 2007
(4/12/2007 TRANSMITTAL ATTACHED)
Author: JEFFREY A HAMEL WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
Doc Date: 03/01/2007
File Break: 03 .06
# of Pages: 3
273522 COMMENTS OF PERFORMING PRPS RELATING TO REMEDY REVIEW BOARD PROCESS
Author: SUTTON BROOK SITE PERFORMING PRPS
Addressee:
NATIONAL REMEDY REVIEW BOARD
Doc Type: MEMO
Doc Date: 03/27/2007 # of Pages: 10
File Break: 03 .06
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10/1/2007
Page 14 of 24
03: REMEDIAL INVESTIGATION (RI)
273523 REMEDY REVIEW BOARD PACKAGE
Author: JAY NAPARSTEK MA DEPT OF ENVIRONMENTAL PROTECTION
Addressee: DON MCELROY US EPA REGION 1
Doc Type: LETTER
Doc Date: 03/27/2007 # of Pages: 2
File Break: 03 .06
273573 MONTHLY PROGRESS REPORT, REMEDIAL INVESTIGATION / FEASIBILITY STUDY (RI/FS) APRIL 2007
(5/14/2007 TRANSMITTAL ATTACHED)
Author: JEFFREY A HAMEL WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: REPORT
Doc Date: 04/01/2007
File Break: 03 .06
# of Pages: 4
273578 REMEDIAL INVESTIGATION AND FEASIBILTY STUDY (RI/FS), VOLUME 3 OF 5, REMEDIAL
INVESTIGATION / FEASIBILITY STUDY (RI/FS) BASELINE RISK ASSESSMENT
Author:
Addressee:
WOODARD & CURRAN
Doc Type: REMEDIAL INVESTIGATION (RI)
REM INVEST/FS STUDY (RI/FS)
REPORT
Doc Date: 05/01/2007 # of Pages: 499
File Break: 03.10
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03: REMEDIAL INVESTIGATION (RI)
273579 REMEDIAL INVESTIGATION AND FEASIBILTY STUDY (RI/FS), VOLUME 4 OF 5, REMEDIAL
INVESTIGATION / FEASIBILITY STUDY (RI/FS) BASELINE RISK ASSESSMENT, APPENDICES
Author: WOODARD & CURRAN
Addressee:
Doc Type: REM INVEST/FS STUDY (RI/FS)
REMEDIAL INVESTIGATION (RI)
REPORT
04: FEASIBILITY STUDY (FS)
273537 RESPONSES TO EPA'S MARCH 14, 2007 COMMENTS ON THE PHASE 2 FEASIBILITY STUDY (FS)
Author: WOODARD & CURRAN
Addressee:
Doc Type: MEMO
273534 REVIEW BY EPA OF PHASE 1 FEASIBILITY STUDY (FS) DEVELOPMENT AND INITIAL SCREENING OF
ALTERNATIVES REPORT
Author: US EPA REGION 1
Addressee:
Doc Type: MEMO
10/1/2007
Page 15 of 24
Doc Date: 05/01/2007 # of Pages: 2834
File Break: 03.10
Doc Date: 01/01/1111 #ofPages: 9
File Break: 04.06
Doc Date: 09/22/2006 # of Pages: 7
File Break: 04.06
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10/1/2007
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04: FEASIBILITY STUDY (FS)
273536 RESPONSES TO COMMENTS ON THE PHASE 1 FEASIBILITY STUDY (FS) DEVELOPMENT AND INTIAL
SCREENING OF ALTERNATIVES REPORT
Author: JEFFREY A HAMEL WOODARD & CURRAN
Addressee: DON MCELROY US EPA REGION 1
Doc Type: LETTER
Doc Date: 12/15/2006 # of Pages: 72
File Break: 04.06
273535 REVIEW OF PHASE 2 FEASIBILITY STUDY (FS) DETAILED ANALYSIS OF ALTERNATIVE REPORT
Author: US EPA REGION 1
Addressee:
Doc Type: MEMO
Doc Date: 03/01/2007 # of Pages: 4
File Break: 04.06
273580 REMEDIAL INVESTIGATION AND FEASIBILTY STUDY (RI/FS), VOLUME 5 OF 5, FEASIBILITY STUDY (FS)
Author: WOODARD & CURRAN
Addressee:
Doc Date: 05/01/2007 # of Pages: 414
File Break: 04.06
Doc Type: REPORT
REM INVEST/FS STUDY (RI/FS)
FEASIBILITY STUDY (FS)
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04: FEASIBILITY STUDY (FS)
273525 PROPOSED PLAN
Author: US EPA REGION 1
Addressee:
Doc Type: PROPOSED PLAN
REPORT
05: RECORD OF DECISION (ROD)
278200 RESPONSES TO NATIONAL REMEDY REVIEW BOARD (NRRB) RECOMMENDATIONS
Author: DON MCELROY US EPA REGION 1 Doc Date: 06/18/2007 # of Pages: 6
Addressee: DAVIDE COOPER US EPA File Break: 05.03
Doc Type: MEMO
278203 COMMENTS ON PROPOSED PLAN
10/1/2007
Page 17 of 24
Doc Date: 06/01/2007 # of Pages: 26
File Break: 04.09
Author: ROBERT FOWLER TEWKSBURY (MA) TOWN OF
Addressee: DON MCELROY US EPA REGION 1
Doc Type: LETTER
Doc Date:
File Break:
07/10/2007 # of Pages: 2
05.03
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10/1/2007
Page 18 of 24
05: RECORD OF DECISION (ROD)
278214 COMMENTS ON PROPOSED PLAN
Author: DOUGLAS W SEARS TEWKSBURY (MA) RESIDENT
Addressee: DON MCELROY US EPA REGION 1
Doc Type: LETTER
278215 COMMENTS ON PROPOSED PLAN
Author: ROBERT BRIGGS TEWKSBURY (MA) TOWN OF - BOARD OF HEALTH
Addressee: PHILLIP FRENCH TEWKSBURY (MA) TOWN OF - BOARD OF HEALTH
CHRISTINE KINNON TEWKSBURY (MA) TOWN OF - BOARD OF HEALTH
RALPH MCHATTON TEWKSBURY (MA) TOWN OF - BOARD OF HEALTH
EDWARD SHEEHAN TEWKSBURY (MA) TOWN OF - BOARD OF HEALTH
DON MCELROY US EPA REGION 1
Doc Type: LETTER
278217 COMMENTS ON PROPOSED PLAN
Author: JAMES R MICELI MA SENATE
Addressee: DON MCELROY US EPA REGION 1
Doc Type: MEMO
AR Collection: 11866
ROD Admin. Record
AR Collection QA Report
***For External Use***
Doc Date: 07/24/2007 # of Pages: 2
File Break: 05.03
Doc Date: 07/25/2007 # of Pages: 1
File Break: 05.03
Doc Date: 07/26/2007 # of Pages: 2
File Break: 05.03
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Page 19 of 24
05: RECORD OF DECISION (ROD)
278201 COMMENTS ON PROPOSED PLAN
Author: RICH DOHERTY ENGINEERING & CONSULTING RESOURCES, INC
Addressee: TOXIC INC
DON MCELROY US EPA REGION 1
Doc Type: LETTER
278216 COMMENTS ON PROPOSED PLAN
Author: SCOTT DARLING III MASSACHUSETTS BAY TRANSPORTATION AUTHORITY
Addressee: DON MCELROY US EPA REGION 1
Doc Type: LETTER
278211 COMMENTS ON PROPOSED PLAN
AR Collection: 11866
ROD Admin. Record
AR Collection QA Report
***For External Use***
Doc Date: 07/27/2007 # of Pages: 9
File Break: 05.03
Doc Date: 07/27/2007 # of Pages: 5
File Break: 05.03
Author: CHARLES HOLMES TEWKSBURY (MA) RESIDENT
Addressee: DON MCELROY US EPA REGION 1
Doc Type: LETTER
Doc Date:
File Break:
07/28/2007 # of Pages: 1
05.03
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ROD Admin. Record Page 20 of 24
AR Collection QA Report
***For External Use***
05: RECORD OF DECISION (ROD)
278209 COMMENTS ON PROPOSED PLAN
Author: ROBERT C KIRSCH WILMER CUTLER PICKERING HALE & DORR
Addressee: DON MCELROY US EPA REGION 1
Doc Type: LETTER
Doc Date: 07/30/2007 # of Pages: 8
File Break: 05.03
278202 COMMENTS ON PROPOSED PLAN
Author: JAY NAPARSTEK MA DEPT OF ENVIRONMENTAL PROTECTION Doc Date: 07/31/2007 # of Pages: 2
Addressee: DON MCELROY US EPA REGION 1 File Break: 05.03
Doc Type: LETTER
278221 RECORD OF DECISION (ROD)
Author: US EPA REGION 1
Addressee:
Doc Date: 09/27/2007 # of Pages: 291
File Break: 05 .04
Doc Type: RECORD OF DECISION (ROD)
DECISION DOCUMENT
REPORT
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10/1/2007
Page 21 of 24
05: RECORD OF DECISION (ROD)
278210 COMMENTS ON PROPOSED PLAN
Author: BILL CONNORS TEWKSBURY (MA) RESIDENT
Addressee: DON MCELROY US EPA REGION 1
Doc Type: LETTER
Doc Date: 01/01/9999
File Break: 05.03
# of Pages: 1
278212 COMMENTS ON PROPOSED PLAN
Author: TIMOTHY SHEA TEWKSBURY (MA) RESIDENT
Addressee: DON MCELROY US EPA REGION 1
Doc Type: LETTER
Doc Date: 01/01/9999
File Break: 05.03
# of Pages: 1
278213 COMMENTS ON PROPOSED PLAN
Author: JAYNE MILLER TEWKSBURY (MA) RESIDENT
Addressee: PETER L MILLER III TEWKSBURY (MA) RESIDENT
DON MCELROY US EPA REGION 1
Doc Date: 01/01/9999
File Break: 05.03
# of Pages: 1
Doc Type: LETTER
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AR Collection QA Report
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10/1/2007
Page 22 of 24
13: COMMUNITY RELATIONS
275026 PUBLIC NOTICE - PROPOSED CLEANUP PLAN
Author: US EPA REGION 1
Addressee:
Doc Type: PRESS RELEASE
PUBLIC NOTICE
Doc Date: 06/15/2007 # of Pages: 2
File Break: 13.03
277698 TRANSCRIPT OF THE PUBLIC MEETING HELD JULY 18, 2007
Author: US EPA REGION 1
Addressee:
Doc Type: PUBLIC MEETING RECORD
Doc Date: 07/18/2007 # of Pages: 14
File Break: 13.04
14: CONGRESSIONAL RELATIONS
278204 CONCERNS OVER LACK OF LARGER PRP GROUP AND ACCESS TO SITE
Author: JEROME E SELISSEN TEWKSBURY (MA) TOWN OF Doc Date: 07/25/2007 # of Pages: 2
Addressee: EDWARD M KENNEDY US SENATE File Break: 14.01
Doc Type: LETTER
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Page 23 of 24
14: CONGRESSIONAL RELATIONS
278205 CONCERNS OVER LACK OF LARGER PRP GROUP AND ACCESS TO SITE
Author: JEROME E SELISSEN TEWKSBURY (MA) TOWN OF
Addressee: JOHNF KERRY US SENATE
Doc Type: LETTER
278206 CONCERNS OVER LACK OF LARGER PRP GROUP AND ACCESS TO SITE
Author: JEROME E SELISSEN TEWKSBURY (MA) TOWN OF Doc Date: 07/26/2007 # of Pages: 2
Addressee: BARRY R FINEGOLD MA HOUSE OF REPRESENTATIVES File Break: 14 01
Doc Type: LETTER
278207 CONCERNS OVER LACK OF LARGER PRP GROUP AND ACCESS TO SITE
AR Collection: 11866
ROD Admin. Record
AR Collection QA Report
***For External Use***
Doc Date: 07/26/2007 # of Pages: 2
File Break: 14.01
Author: JEROME E SELISSEN TEWKSBURY (MA) TOWN OF
Addressee: jAMESRMICELI MA SENATE
Doc Type: LETTER
Doc Date:
File Break:
07/26/2007 # of Pages: 2
14.01
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10/1/2007
Page 24 of 24
14: CONGRESSIONAL RELATIONS
278208 CONCERNS OVER LACK OF LARGER PRP GROUP AND ACCESS TO SITE
Author: JEROME E SELISSEN TEWKSBURY (MA) TOWN OF Doc Date: 07/26/2007 # of Pages: 2
Addressee: SUSAN TUCKER MA SENATE File Break: 14.01
Doc Type: LETTER
AR Collection: 11866
ROD Admin. Record
AR Collection QA Report
***For External Use***
Number of Documents in Collection: 81
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EPA Region 1 AR Compendium GUIDANCE DOCUMENTS
EPA guidance documents may be reviewed at the EPA Region I Superfund Records Center in
Boston, Massachusetts.
TITLE
INTERIM FINAL GUIDANCE FOR CONDUCTING REMEDIAL INVESTIGATIONS AND FEASIBILITY STUDIES UNDER CERCLA.
DOCDATE OSWER/EPA ID DOCNUMBER
10/1/1988 OSWER #9355.3-01 2002
TITLE
RISK ASSESSMENT GUIDANCE FOR SUPERFUND, VOLUME II, ENVIRONMENTAL EVALUATION MANUAL
DOCDATE OSWER/EPA ID DOCNUMBER
3/1/1989 EPA/540/1-89/001 5024
TITLE
RISK ASSESSMENT GUIDANCE FOR SUPERFUND. VOLUME I. HUMAN HEALTH EVALUATION MANUAL (PART A). INTERIM FINAL.
DOCDATE OSWER/EPA ID DOCNUMBER
12/1 /1989 E PA 540/1 -89/002 C174
TITLE
STREAMLINING THE RI/FS FOR CERCLA MUNICIPAL LANDFILL SITES.
DOCDATE OSWER/EPA ID DOCNUMBER
9/1/1990 OSWER 9355.3-11FS C176
TITLE
CONDUCTING REMEDIAL INVESTIGATIONS/FEASIBILITY STUDIES FOR CERCLA MUNICIPAL LANDFILL SITES.
DOCDATE OSWER/EPA ID DOCNUMBER
2/1/1991 OSWER 9355.3-11 C177
TITLE
ECOLOGICAL ASSESSMENT OF HAZARDOUS WASTE SITES: A FIELD AND LABORATORY REFERENCE.
DOCDATE OSWER/EPA ID DOCNUMBER
3/1/1989 EPA 600/3-89/013 C251
TITLE
ECO UPDATE. ECOTOX THRESHOLDS. INTERMITTENT BULLETIN VOLUME 3, NUMBER 2
DOCDATE OSWER/EPA ID DOCNUMBER
1/1/1996 OSWER 9345.0-12FSI C269
TITLE
LAND USE IN THE CERCLA REMEDY SELECTION PROCESS
DOCDATE OSWER/EPA ID DOCNUMBER
1/1/1995 OSWER 9355.7-04 C317
TITLE
EXPOSURE FACTORS HANDBOOK; GENERAL FACTORS, VOLUME I
DOCDATE OSWER/EPA ID DOCNUMBER
8/1/1997 EPA 600/P-95/002FA C356
TITLE
ECOLOGICAL RISK ASSESSMENT GUIDANCE FOR SUPERFUND PROCESS FOR DESIGNING AND CONDUCTING ECOLOGICAL RISK
ASSESSMENTS (EPA 540-R-97-006)
DOCDATE OSWER/EPA ID DOCNUMBER
6/2/1997 C361
TITLE
FRAMEWORK FOR ECOLOGICAL RISK ASSESSMENT (EPA/630/R-92/001)
DOCDATE OSWER/EPA ID DOCNUMBER
2/1/1992 EPA 630/R-92-001 C364
Wednesday, June 27, 2007
Page 1
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EPA Region 1 AR Compendium GUIDANCE DOCUMENTS
EPA guidance documents may be reviewed at the EPA Region I Superfund Records Center in
Boston, Massachusetts.
TITLE
DRAFT FINAL GUIDELINES FOR ECOLOGICAL RISK ASSESSMENT
DOCDATE OSWER/EPA ID DOCNUMBER
7/18/1997 C366
TITLE
FRAMEWORK FOR ECOLOGICAL RISK ASSESSMENT AT THE EPA
DOCDATE OSWER/EPA ID DOCNUMBER
1/1/1992 C396
TITLE
ROLE OF BTAG'S IN ECOLOGICAL ASSESSMENT -ECO UPDATE - VOL. 1, NO. 1
DOCDATE OSWER/EPA ID DOCNUMBER
9/1/1991 OSWER 9345.0-05I C416
TITLE
HEALTH EFFECTS ASSESSMENT SUMMARY TABLES - FY 1997 UPDATE
DOCDATE OSWER/EPA ID DOCNUMBER
7/1/1997 EPA 540/R-97-036 C468
TITLE
DERMAL EXPOSURE ASSESSMENT: PRINCIPLES AND APPLICATIONS
DOCDATE OSWER/EPA ID DOCNUMBER
1/1/1992 EPA 600/8-91-011B C469
TITLE
DRAFT INTERIM FINAL OSWER MONITORED NATURAL ATTENUATION POLICY
DOCDATE OSWER/EPA ID DOCNUMBER
12/1/1997 OSWER 9200.4-17 C474
TITLE
LETTER AND ATTACHED MEMORADUM OF AGREEMENT BETWEEN U.S. EPA AND MASS DEP FOR IMPLEMENTATION OF GROUND WATER
USE AND VALUE DETERMINATION GUIDANCE
DOCDATE OSWER/EPA ID DOCNUMBER
3/23/1998 C477
TITLE
PRESUMPTIVE REMEDIES: SITE CHARACTERIZATION AND TECHNOLOGY SELECTION FOR CERCLA SITES WITH VOLATILE ORGANIC
COMPOUNDS IN SOILS
DOCDATE OSWER/EPA ID DOCNUMBER
9/1/1993 OSWER 9355.0-48FS C491
TITLE
EXPOSURE FACTORS HANDBOOK; FOOD INGESTION FACTORS, VOLUME I
DOCDATE OSWER/EPA ID DOCNUMBER
8/1/1997 E P A/600/P-95/002F B C501
TITLE
EXPOSURE FACTORS HANDBOOK; ACTIVITY FACTORS, VOLUME I
DOCDATE OSWER/EPA ID DOCNUMBER
8/1/1997 E P A/600/P-95/002F C C502
TITLE
USE OF MONITORED NATURAL ATTENTUATION AT SUPERFUND, RCRA CORRECTIVE ACTION, AND UNDERGROUND STORAGE TANK SITES
DOCDATE OSWER/EPA ID DOCNUMBER
4/21/1999 OSWER 9200.4-17P C515
Wednesday, June 27, 2007 Page 2
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EPA Region 1 AR Compendium GUIDANCE DOCUMENTS
EPA guidance documents may be reviewed at the EPA Region I Superfund Records Center in
Boston, Massachusetts.
TITLE
REVISED ALTERNATIVE CAP DESIGN GUIDANCE PROPOSED FOR UNLINED HAZARDOUS WASTE LANDFILLS IN THE EPA REGION I
DOCDATE OSWER/EPA ID DOCNUMBER
2/5/2001 C524
TITLE
GUIDE TO PREPARING SUPERFUND PROPOSED PLANS RECORDS OF DECISION AND OTHER REMEDY SELECTION DECISION DOCUMENTS
DOCDATE OSWER/EPA ID DOCNUMBER
7/1/1999 OSWER 9200.1-23P C525
TITLE
RISK ASSESSMENT GUIDANCE FOR SUPERFUND, VOLUME 1, HUMAN HEALTH EVALUATION MANUAL, INTERIM
DOCDATE OSWER/EPA ID DOCNUMBER
1/1/1998 OSWER 9285.7-01 D C530
TITLE
WILDLIFE EXPOSURE FACTORS HANDBOOK, VOLUME 2 OF 2
DOCDATE OSWER/EPA ID DOCNUMBER
12/1/1993 EPA 600/R-93/187 C567
TITLE
SOIL SCREENING GUIDANCE: USER'S GUIDE
DOCDATE OSWER/EPA ID DOCNUMBER
7/1/1996 OSWER NO. 9355.4-23 C577
TITLE
RISK ASSESSMENT GUIDANCE FOR SUPERFUND VOLUME I: HUMAN HEALTH EVALUATION MANUAL. PART D. STANDARDIZED PLANNING,
REPORTING, AND REVIEW OF SUPERFUND RISK ASSESSMENTS. FINAL
DOCDATE OSWER/EPA ID DOCNUMBER
12/1/2001 C593
TITLE
CALCULATING UPPER CONFIDENCE LIMITS FOR EXPOSURE POINT CONCENTRATIONS AT HAZARDOUS WASTE SITES
DOCDATE OSWER/EPA ID DOCNUMBER
12/1/2002 C596
TITLE
RISK ASSESSMENT GUIDANCE FOR SUPERFUND VOLUME I: HUMAN HEALTH EVALUATION MANUAL (PART E SUPPLEMENTAL GUIDANCE
FOR DERMAL RISK ASSESSMENT) FINAL
DOCDATE OSWER/EPA ID DOCNUMBER
7/1/2004 C602
TITLE
GUIDELINES FOR ECOLOGICAL RISK ASSESSMENT
DOCDATE OSWER/EPA ID DOCNUMBER
4/1/1998 C614
TITLE
RISK ASSESSMENT GUIDANCE FOR SUPERFUND. VOL 1. HUMAN HEALTH EVALUATION MANUAL (PART B, DEVELOPMENT OF RISK-BASED
PRELIMINARY REMEDIATION GOALS) INTERIM
DOCDATE OSWER/EPA ID DOCNUMBER
12/1/1991 OSWER 9285.6-03 C644
TITLE
GUIDANCE FOR CHARACTERIZING BACKGROUND CHEMICALS IN SOIL AT SUPERFUND SITES EXTERNAL REVIEW DRAFT
DOCDATE OSWER/EPA ID DOCNUMBER
6/1/2001 OSWER 9285.7-41 C645
Wednesday, June 27, 2007
Page 3
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EPA Region 1 AR Compendium GUIDANCE DOCUMENTS
EPA guidance documents may be reviewed at the EPA Region I Superfund Records Center in
Boston, Massachusetts.
TITLE
ISSUANCE OF FINAL GUIDANCE: ECOLOGICAL RISK ASSESSMENT AND RISK MANAGEMENT PRINCIPLES FOR SUPERFUND SITES
DOCDATE OSWER/EPA ID DOCNUMBER
10/7/1999 OSWER 9285.7-28 P C646
Wednesday, June 27, 2007
Page 4
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